Add snooze: put a conversation away, and bring it back

Snooze is archive-with-a-timer, expressed in labels like everything else
— Inbox off, Snoozed on — so the "a message carries at least one label"
invariant holds without a second mechanism, and the snoozed pile is
reachable by every path that already works on labels.

The web endpoint was the broken half. POST /status/thread/{id}/snooze
wrote snoozedUntil and nothing else: no labels moved and nothing
propagated, so the conversation stayed in the Inbox both locally and at
the provider while its row vanished from the list — and then the sweep
"woke" a thread that had never left. Both callers now go through
ThreadSnoozeService, so a snooze means the same thing whichever client
set it. ThreadSnoozeEndpointTest asserts on labels rather than on the
column, because the column was always written correctly and a test that
checked it would have passed against the broken implementation.

The UI was missing outright. The row button called an action whose
`until` defaulted to null and which Stimulus calls with the event alone,
so it cleared a snooze instead of setting one; the toolbar hardcoded
"tomorrow 8am" behind a comment asking for a picker. Both now open a
menu. The wake times are computed in the browser, deliberately: the
server has no timezone for the session, so "tomorrow morning" resolved
server-side would mean tomorrow morning wherever the container thinks it
is. "Later today" drops itself once the evening has passed rather than
resolving to a time already gone.

The Snoozed pile also had nowhere to live — no route and no sidebar
entry, so it was unreachable. Both added, gated on there being something
snoozed, on the same reasoning as Archive.

Thread/set is a plMail extension; RFC 8621's Thread is read-only. It
accepts exactly one property and refuses create and destroy outright:
threads come into being by mail arriving, and a client that could conjure
one would be describing something nothing else understands. Unlike the
web endpoint it refuses an unparseable date rather than substituting
"in 1 day" — for an API, a client told its write succeeded would find the
thread back at a time it never chose.

app:mail:wake-snoozed runs every minute, which is the unit people pick a
wake time in, and costs one indexed query when nothing is due.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

assets/controllers/mail/list_toolbar_controller.js

@@ -148,15 +148,18 @@ export default class extends Controller {
         await this._bulkPost(ids, "read", { read: false });
     }
 
-    async snoozeSelected() {
+    /**
+     * The wake time arrives as a param from the snooze menu (mail--snooze-menu),
+     * which computes it in the browser — the server has no timezone for the
+     * session. Absent, this clears the snooze on the selection.
+     */
+    async snoozeSelected(event) {
         const ids = this._selectedIds();
         if (ids.length === 0) { return; }
-        // Default: snooze until tomorrow morning.
-        // Replace with a date-picker dispatch if you add a snooze UI.
-        const tomorrow = new Date();
-        tomorrow.setDate(tomorrow.getDate() + 1);
-        tomorrow.setHours(8, 0, 0, 0);
-        await this._bulkPost(ids, "snooze", { until: tomorrow.toISOString() });
+
+        const { until = null } = event?.params ?? {};
+
+        await this._bulkPost(ids, "snooze", { until });
     }
 
     // ── Private ───────────────────────────────────────────────────────────

assets/controllers/mail/message_row_controller.js

@@ -51,8 +51,18 @@ export default class extends Controller {
         await this.#post(trashUrl);
     }
 
-    async snooze(event, until = null) {
-        const { snoozeUrl } = event.params;
+    /**
+     * The wake time arrives as a param, set by the snooze menu — see
+     * mail--snooze-menu, which computes it in the browser because the server
+     * has no timezone for the session.
+     *
+     * Absent, this clears the snooze. That used to be the *only* behaviour:
+     * the signature took `until = null` as a second argument, and Stimulus
+     * calls actions with the event alone, so the row's snooze button silently
+     * unsnoozed instead of snoozing.
+     */
+    async snooze(event) {
+        const { snoozeUrl, until = null } = event.params;
         event.stopPropagation();
 
         await this.#post(snoozeUrl, { until });

assets/controllers/mail/snooze_menu_controller.js

@@ -0,0 +1,73 @@
+import { Controller } from "@hotwired/stimulus";
+import { snoozeOptions } from "../../snooze_options.js";
+
+/**
+ * Fills a snooze menu with concrete wake times.
+ *
+ * The times cannot come from Twig: the server has no timezone for the session,
+ * so "tomorrow morning" rendered server-side would mean tomorrow morning in
+ * whatever zone the container thinks it is in. The markup therefore ships the
+ * labels — which are translated, and must be — and this fills in the instants.
+ *
+ * It only sets params; the click itself is handled by mail--message-row#snooze
+ * or mail--list-toolbar#snoozeSelected, so the posting, the CSRF header and the
+ * Turbo Stream handling all stay in one place per surface.
+ *
+ * Options are recomputed on every open rather than once on connect. A list left
+ * open across midnight would otherwise offer a "tomorrow" that is today.
+ */
+export default class extends Controller {
+    static targets = ["option"];
+
+    connect() {
+        this.refresh();
+    }
+
+    refresh() {
+        const options = snoozeOptions();
+        const byKey = new Map(options.map((option) => [option.key, option.at]));
+
+        for (const element of this.optionTargets) {
+            const at = byKey.get(element.dataset.snoozeKey);
+
+            // "Later today" disappears once the evening has passed, so a target
+            // with no matching option is expected rather than an error.
+            if (undefined === at) {
+                element.hidden = true;
+                continue;
+            }
+
+            element.hidden = false;
+
+            // setAttribute, not dataset: the identifiers contain a double dash
+            // ("mail--message-row"), which has no faithful camelCase form and
+            // so cannot be round-tripped through the dataset API.
+            //
+            // Both are set unconditionally. Only one has a controller listening
+            // on any given surface, and the unused attribute is inert — cheaper
+            // than teaching this controller which surface it is on.
+            element.setAttribute("data-mail--message-row-until-param", at.toISOString());
+            element.setAttribute("data-mail--list-toolbar-until-param", at.toISOString());
+
+            const when = element.querySelector("[data-snooze-when]");
+
+            if (null !== when) {
+                when.textContent = this.#format(at);
+            }
+        }
+    }
+
+    // ── Private ───────────────────────────────────────────────────────────
+
+    /**
+     * "Sat 08:00" — weekday and time, no date. The label above it already says
+     * which day in words; this is the confirmation, not the primary reading.
+     */
+    #format(date) {
+        return date.toLocaleString(document.documentElement.lang || undefined, {
+            weekday: "short",
+            hour: "2-digit",
+            minute: "2-digit",
+        });
+    }
+}

assets/controllers/ui/dropdown_controller.js

@@ -32,6 +32,11 @@ export default class extends Controller {
     open() {
         this.menuTarget.hidden = false;
 
+        // For menus whose contents go stale while closed — the snooze menu
+        // recomputes its wake times here, so one left open across midnight
+        // cannot offer a "tomorrow" that is already today.
+        this.dispatch("opened", { target: this.menuTarget });
+
         document.addEventListener("click", this._boundOutside, { capture: true });
         document.addEventListener("keydown", this._boundEscape);
     }

assets/snooze_options.js

@@ -0,0 +1,70 @@
+/**
+ * The wake times offered by the snooze menus.
+ *
+ * Shared by the per-row menu and the list toolbar so the two cannot drift —
+ * "Tomorrow" meaning 8am in one place and 9am in the other is the kind of
+ * difference nobody reports and everybody notices.
+ *
+ * Computed in the browser, deliberately. The server never sees a timezone for
+ * the session, so "tomorrow morning" resolved server-side would mean tomorrow
+ * morning wherever the container happens to think it is. The endpoint takes an
+ * absolute instant and stays ignorant of what the user called it.
+ */
+
+/** Morning, for every option that lands on a future day. */
+const MORNING_HOUR = 8;
+
+/** "Later today" is a nudge, not a date — it only exists while it still fits. */
+const LATER_TODAY_HOUR = 18;
+
+function at(date, hour) {
+    const result = new Date(date);
+    result.setHours(hour, 0, 0, 0);
+    return result;
+}
+
+function addDays(date, days) {
+    const result = new Date(date);
+    result.setDate(result.getDate() + days);
+    return result;
+}
+
+/**
+ * Days until the coming Saturday. Today counts as "this weekend" only if it is
+ * not already Saturday or Sunday — on those, "this weekend" is now, which is
+ * not a snooze, so it rolls to the next one.
+ */
+function daysUntilSaturday(now) {
+    const day = now.getDay(); // 0 Sun … 6 Sat
+    const delta = (6 - day + 7) % 7;
+    return 0 === delta ? 7 : delta;
+}
+
+/** Days until the coming Monday. */
+function daysUntilMonday(now) {
+    const delta = (1 - now.getDay() + 7) % 7;
+    return 0 === delta ? 7 : delta;
+}
+
+/**
+ * @param {Date} [now]
+ * @returns {{ key: string, at: Date }[]} in menu order, soonest first
+ */
+export function snoozeOptions(now = new Date()) {
+    const options = [];
+
+    // Dropped rather than pushed to tomorrow once the evening has passed: an
+    // option labelled "later today" that resolves to a time already gone would
+    // fire on the very next sweep.
+    const laterToday = at(now, LATER_TODAY_HOUR);
+
+    if (laterToday > now) {
+        options.push({ key: "later_today", at: laterToday });
+    }
+
+    options.push({ key: "tomorrow", at: at(addDays(now, 1), MORNING_HOUR) });
+    options.push({ key: "this_weekend", at: at(addDays(now, daysUntilSaturday(now)), MORNING_HOUR) });
+    options.push({ key: "next_week", at: at(addDays(now, daysUntilMonday(now)), MORNING_HOUR) });
+
+    return options;
+}

src/Command/Maintenance/WakeSnoozedCommand.php

@@ -0,0 +1,82 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Command\Maintenance;
+
+use App\Repository\Mail\MessageThreadRepository;
+use App\Service\Mail\ThreadSnoozeService;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Component\Console\Attribute\AsCommand;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+
+/**
+ * Returns snoozed conversations to the Inbox once their time is up.
+ *
+ * This is the half of snooze that makes it a snooze rather than a filing
+ * cabinet: without it a snoozed thread leaves the inbox and never comes back.
+ * It is scheduled every minute — the unit a user picks a wake time in — and is
+ * cheap when there is nothing due, which is almost always.
+ *
+ * Idempotent, and safe to run concurrently with itself: waking an already-woken
+ * thread only re-asserts the Inbox label. That matters because the scheduler
+ * replays a missed run when a worker comes back up.
+ */
+#[AsCommand(
+    name: 'app:mail:wake-snoozed',
+    description: 'Return snoozed conversations to the inbox once their wake time has passed.',
+)]
+final class WakeSnoozedCommand extends Command
+{
+    /**
+     * Per run, so one enormous backlog cannot hold the worker for minutes.
+     * Whatever is left is picked up by the next run a minute later.
+     */
+    private const int BATCH = 200;
+
+    public function __construct(
+        private readonly MessageThreadRepository $threadRepository,
+        private readonly ThreadSnoozeService $snoozeService,
+        private readonly EntityManagerInterface $entityManager,
+    ) {
+        parent::__construct();
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output);
+        $due = $this->threadRepository->findDueSnoozed(new \DateTimeImmutable(), self::BATCH);
+
+        if ([] === $due) {
+            return Command::SUCCESS;
+        }
+
+        $woken = 0;
+
+        foreach ($due as $thread) {
+            try {
+                $this->snoozeService->wake($thread);
+                ++$woken;
+            } catch (\Throwable $error) {
+                // One thread that cannot be woken — a deleted account, a
+                // provider that rejected the label change — must not strand
+                // every other thread behind it. The snooze stays set, so the
+                // next run tries again.
+                $io->warning(sprintf(
+                    'Could not wake thread %d: %s',
+                    (int) $thread->getId(),
+                    $error->getMessage(),
+                ));
+
+                $this->entityManager->clear();
+            }
+        }
+
+        $io->success(sprintf('Woke %d conversation(s).', $woken));
+
+        return Command::SUCCESS;
+    }
+}

src/Controller/Mail/MailController.php

@@ -203,6 +203,33 @@ final class MailController extends AbstractController
         ]);
     }
 
+    /**
+     * Snoozed role view — where conversations wait for their wake time.
+     *
+     * Ordered by lastMessageAt like every other list rather than by wake time,
+     * which is the less obvious choice: the row shows when it comes back, so
+     * sorting by it would be legible. But this list is reached to *find* a
+     * conversation, and "the one from Tuesday" is how people look, not "the
+     * one due third".
+     */
+    #[Route('/snoozed', name: 'snoozed')]
+    public function snoozed(Request $request): Response
+    {
+        $user  = $this->getUser();
+        $page  = max(1, (int) $request->query->get('page', 1));
+        $threads = $this->threadRepository->findForRole($user, LabelRole::Snoozed, $page);
+        $total   = $this->threadRepository->countForRole($user, LabelRole::Snoozed);
+
+        $this->threadRepository->preloadLabels($threads);
+
+        return $this->render('mail/snoozed.html.twig', [
+            'threads'  => $threads,
+            'page'     => $page,
+            'total'    => $total,
+            'per_page' => 50,
+        ]);
+    }
+
     #[Route('/account/{account}/folders', name: 'account_folders')]
     public function accountFolders(Account $account): Response
     {

src/Controller/Mail/ThreadStatusController.php

@@ -17,6 +17,7 @@ use App\Repository\Mail\MessageThreadRepository;
 use App\Service\Label\LabelChangePropagator;
 use App\Service\Label\LabelResolver;
 use App\Service\Label\ThreadLabelSynchronizer;
+use App\Service\Mail\ThreadSnoozeService;
 use DateTimeImmutable;
 use Doctrine\ORM\EntityManagerInterface;
 use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
@@ -48,6 +49,7 @@ class ThreadStatusController extends AbstractController
         private readonly LabelChangePropagator   $propagator,
         private readonly ThreadLabelSynchronizer $threadLabelSynchronizer,
         private readonly StateManager            $stateManager,
+        private readonly ThreadSnoozeService     $snoozeService,
     ) {}
 
     #[Route('/star', name: 'star', methods: ['POST'])]
@@ -211,19 +213,34 @@ class ThreadStatusController extends AbstractController
         $body  = json_decode($request->getContent(), true);
         $until = null;
 
-        if (true === array_key_exists('until', $body)) {
+        if (true === is_array($body) && true === array_key_exists('until', $body)) {
             if (null !== $body['until']) {
                 try {
-                    $until = new DateTimeImmutable($body['until']);
-                } catch (\Exception $e) {
+                    $until = new DateTimeImmutable((string) $body['until']);
+                } catch (\Exception) {
                     $until = new DateTimeImmutable('in 1 day');
                 }
             }
         }
 
-        $thread->setSnoozedUntil($until);
-        $this->recordJmapUpdates($messages);
-        $this->em->flush();
+        // Through the service, not setSnoozedUntil(): snoozing has to move the
+        // Inbox label off and propagate that outward. Writing the column here
+        // is what this endpoint used to do, and it left the conversation
+        // sitting in the inbox — locally and at the provider — while the row
+        // vanished from the list, until the sweep "woke" a thread that had
+        // never left. Thread/set goes through the same service for the same
+        // reason. The one deliberate difference is above: a form post gets the
+        // "in 1 day" fallback on an unparseable date, where the JMAP method
+        // refuses it — see ThreadSetMethod::snoozeDate().
+        if (null === $until) {
+            $this->snoozeService->wake($thread);
+        } else {
+            $this->snoozeService->snooze($thread, $until);
+        }
+
+        // No recordJmapUpdates/flush: the service records its own state
+        // changes and flushes, because the label moves have to be visible to
+        // the propagator jobs it queues.
 
         return $this->renderTurboStream('thread/status/_snooze.stream.html.twig', [
             'thread' => $thread,

src/Domain/Enum/Mail/LabelRole.php

@@ -22,6 +22,17 @@ enum LabelRole: string
     case Trash = 'trash';
     case Spam = 'spam';
     case Archive = 'archive';
+    /**
+     * Where a conversation waits while it is snoozed.
+     *
+     * Unlike the others this has no IMAP special-use and no provider
+     * counterpart — nothing sets it but plMail, and MailboxSpecialUse
+     * therefore never maps to it. It exists so that snoozing is expressible in
+     * the same vocabulary as everything else: a conversation leaves the Inbox
+     * and carries this instead, which keeps the "a message is always in at
+     * least one label" invariant without a second mechanism.
+     */
+    case Snoozed = 'snoozed';
 
     public static function fromSpecialUse(MailboxSpecialUse $specialUse): self
     {
@@ -44,6 +55,7 @@ enum LabelRole: string
             self::Trash => 'Trash',
             self::Spam => 'Spam',
             self::Archive => 'Archive',
+            self::Snoozed => 'Snoozed',
         };
     }
 
@@ -60,6 +72,9 @@ enum LabelRole: string
             self::Spam => 30,
             self::Trash => 40,
             self::Archive => 50,
+            // After Archive, before custom labels: it is a system place, but
+            // the least-visited one.
+            self::Snoozed => 60,
         };
     }
 

src/Infrastructure/Scheduler/MaintenanceSchedule.php

@@ -52,6 +52,12 @@ final class MaintenanceSchedule implements ScheduleProviderInterface
                 // gone degraded.
                 RecurringMessage::cron('0 4 * * *', new RunCommandMessage('app:push:renew --repair')),
 
+                // Snooze is only a snooze if something brings the thread
+                // back. Every minute, because a minute is the unit people
+                // pick a wake time in, and the sweep costs one indexed query
+                // when nothing is due — which is almost always.
+                RecurringMessage::cron('* * * * *', new RunCommandMessage('app:mail:wake-snoozed')),
+
                 // Log entries and dead heartbeats.
                 RecurringMessage::cron('30 4 * * *', new RunCommandMessage('app:monitoring:prune')),
 

src/Jmap/Mapper/MailboxMapper.php

@@ -125,6 +125,11 @@ final class MailboxMapper
             'Starred', 'Flagged' => 'flagged',
             'Important' => 'important',
             'All', 'AllMail' => 'all',
+            // Vendor role: there is no IANA special-use for snoozed, so this
+            // is plMail's own. A standard client reads an unrecognised role
+            // exactly as this method's default does — no role, mailbox still
+            // listed — which is the intended degradation.
+            'Snoozed' => 'snoozed',
             default => null,
         };
     }

src/Jmap/Method/Mail/ThreadGetMethod.php

@@ -77,6 +77,20 @@ final class ThreadGetMethod implements JmapMethod
             $list[] = [
                 'id' => (string) $thread->getId(),
                 'emailIds' => $emailIds,
+                // plMail extension. RFC 8621's Thread has only id and emailIds;
+                // this is the one piece of thread state the product owns, and
+                // the web UI already acts on it. A client that computed snooze
+                // locally instead would disagree with the browser and lose it
+                // on reinstall, which is exactly the case the client guide
+                // names as ask-don't-work-around.
+                //
+                // Null when never snoozed *and* when the snooze has already
+                // expired — a past timestamp is not a state anything should
+                // render, and leaving it would have every client re-implement
+                // the comparison.
+                'snoozedUntil' => $this->utcOrNull(
+                    $thread->isSnoozed() ? $thread->getSnoozedUntil() : null,
+                ),
             ];
         }
 
@@ -87,4 +101,14 @@ final class ThreadGetMethod implements JmapMethod
             'notFound' => array_values(array_diff($requestedIds, $found)),
         ];
     }
+
+    /**
+     * The same shape EmailMapper::utcOrNull emits, and for the same reason:
+     * clients parse this format exactly, and a value left in the server's
+     * local zone would be read as UTC and land hours out.
+     */
+    private function utcOrNull(?\DateTimeImmutable $date): ?string
+    {
+        return $date?->setTimezone(new \DateTimeZone('UTC'))->format('Y-m-d\\TH:i:s\\Z');
+    }
 }

src/Jmap/Method/Mail/ThreadSetMethod.php

@@ -0,0 +1,209 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Jmap\Method\Mail;
+
+use App\Entity\Mail\MessageThread;
+use App\Jmap\Account\AccountResolver;
+use App\Jmap\Method\JmapMethod;
+use App\Jmap\Protocol\Exception\MethodException;
+use App\Jmap\Protocol\JmapContext;
+use App\Jmap\State\JmapObjectType;
+use App\Jmap\State\StateManager;
+use App\Repository\Mail\MessageThreadRepository;
+use App\Service\Mail\ThreadSnoozeService;
+use Doctrine\ORM\EntityManagerInterface;
+
+/**
+ * "Thread/set" — a plMail extension, not RFC 8621.
+ *
+ * The spec's Thread is read-only: it has no /set, because a thread is derived
+ * from its Emails and there is nothing on it to change. plMail's is different
+ * in exactly one way — a thread can be snoozed, and that state belongs to the
+ * thread rather than to any message in it.
+ *
+ * Snoozing is not a flag. Setting `snoozedUntil` moves the conversation out of
+ * the Inbox and into Snoozed, and app:mail:wake-snoozed brings it back later —
+ * see ThreadSnoozeService, which the web UI goes through as well, so a snooze
+ * means the same thing whichever client set it.
+ *
+ * Deliberately narrow. `create` and `destroy` are refused outright: threads
+ * come into being by mail arriving and go away when their last message does,
+ * and a client that could conjure one would be describing something the rest
+ * of the system has no meaning for. `update` accepts one property.
+ *
+ * Standard clients neither know nor need this method — Thread/get still
+ * answers the spec's two properties plus one they will ignore.
+ */
+final class ThreadSetMethod implements JmapMethod
+{
+    private const int MAX_OBJECTS = 500;
+
+    public function __construct(
+        private readonly AccountResolver $accountResolver,
+        private readonly MessageThreadRepository $threadRepository,
+        private readonly StateManager $stateManager,
+        private readonly EntityManagerInterface $entityManager,
+        private readonly ThreadSnoozeService $snoozeService,
+    ) {
+    }
+
+    public function name(): string
+    {
+        return 'Thread/set';
+    }
+
+    public function handle(array $arguments, JmapContext $context): array
+    {
+        $account = $this->accountResolver->resolve($context->user, $arguments['accountId'] ?? null);
+        $accountId = (int) $account->getId();
+
+        $oldState = $this->stateManager->stateFor($accountId, JmapObjectType::Thread);
+
+        foreach (['create', 'destroy'] as $unsupported) {
+            $value = $arguments[$unsupported] ?? null;
+
+            if (null !== $value && [] !== $value) {
+                throw new MethodException(
+                    'invalidArguments',
+                    sprintf('Thread/set does not support "%s".', $unsupported),
+                );
+            }
+        }
+
+        $update = $arguments['update'] ?? [];
+
+        if (false === is_array($update)) {
+            throw new MethodException('invalidArguments', '"update" must be an object.');
+        }
+
+        if (count($update) > self::MAX_OBJECTS) {
+            throw new MethodException(
+                'requestTooLarge',
+                sprintf('At most %d objects per Thread/set.', self::MAX_OBJECTS),
+            );
+        }
+
+        $updated = [];
+        $notUpdated = [];
+
+        foreach ($update as $rawId => $patch) {
+            $id = $context->resolveId((string) $rawId) ?? (string) $rawId;
+
+            // Scoped by account, so another user's thread id resolves to
+            // nothing rather than being reachable by guessing an integer.
+            $threads = $this->threadRepository->findByAccountAndIds($accountId, [(int) $id]);
+            $thread = $threads[0] ?? null;
+
+            if (null === $thread) {
+                $notUpdated[(string) $rawId] = [
+                    'type' => 'notFound',
+                    'description' => 'No such thread in this account.',
+                ];
+
+                continue;
+            }
+
+            try {
+                $this->applyPatch($thread, $patch);
+            } catch (MethodException $error) {
+                $notUpdated[(string) $rawId] = $error->toError();
+
+                continue;
+            }
+
+            // Null: nothing was changed beyond what was asked for, which is
+            // what RFC 8620 §5.3 wants said here. The label moves are not a
+            // server-side surprise — they are what snoozing means.
+            $updated[(string) $id] = null;
+        }
+
+        // No flush here: the snooze service records its own state changes and
+        // flushes, because the label moves it makes have to be visible to the
+        // propagator jobs it queues.
+
+        return [
+            'accountId' => (string) $accountId,
+            'oldState' => $oldState,
+            'newState' => $this->stateManager->stateFor($accountId, JmapObjectType::Thread),
+            'created' => null,
+            'updated' => (object) $updated,
+            'destroyed' => [],
+            'notCreated' => (object) [],
+            'notUpdated' => (object) $notUpdated,
+            'notDestroyed' => (object) [],
+        ];
+    }
+
+    /**
+     * @param mixed $patch the JMAP patch object for one thread
+     *
+     * @throws MethodException when the patch names anything but snoozedUntil
+     */
+    private function applyPatch(MessageThread $thread, mixed $patch): void
+    {
+        if (false === is_array($patch)) {
+            throw new MethodException('invalidPatch', 'Each update must be an object.');
+        }
+
+        foreach (array_keys($patch) as $property) {
+            if ('snoozedUntil' !== $property) {
+                throw new MethodException(
+                    'invalidProperties',
+                    sprintf('"%s" is not a settable Thread property.', (string) $property),
+                );
+            }
+        }
+
+        if (false === array_key_exists('snoozedUntil', $patch)) {
+            // An empty patch is a no-op rather than an error: it changes
+            // nothing, and refusing it would make a client's "apply whatever
+            // changed" loop fail on the case where nothing did.
+            return;
+        }
+
+        $until = $this->snoozeDate($patch['snoozedUntil']);
+
+        // Not a field assignment: snoozing moves the conversation out of the
+        // Inbox and clearing brings it back, both propagated outward. Writing
+        // the column directly would leave a thread marked snoozed and still
+        // sitting in the inbox.
+        if (null === $until) {
+            $this->snoozeService->wake($thread);
+        } else {
+            $this->snoozeService->snooze($thread, $until);
+        }
+    }
+
+    /**
+     * Null clears the snooze — the same convention the web UI's endpoint uses.
+     *
+     * A malformed date is refused rather than coerced. The web endpoint quietly
+     * substitutes "in 1 day" on a parse failure, which is defensible for a form
+     * post and wrong for an API: a client would be told its write succeeded and
+     * find the thread reappearing at a time it never asked for.
+     */
+    private function snoozeDate(mixed $value): ?\DateTimeImmutable
+    {
+        if (null === $value) {
+            return null;
+        }
+
+        if (false === is_string($value) || '' === trim($value)) {
+            throw new MethodException(
+                'invalidProperties',
+                '"snoozedUntil" must be a UTC date-time string or null.',
+            );
+        }
+
+        try {
+            return new \DateTimeImmutable($value);
+        } catch (\Exception) {
+            throw new MethodException(
+                'invalidProperties',
+                sprintf('"%s" is not a parseable date-time.', $value),
+            );
+        }
+    }
+}

src/Repository/Mail/MessageThreadRepository.php

@@ -553,6 +553,52 @@ class MessageThreadRepository extends ServiceEntityRepository
         );
     }
 
+    /**
+     * How many of the user's conversations are snoozed right now.
+     *
+     * Counts the column rather than the Snoozed label, because the column is
+     * what the wake sweep acts on: a thread whose time has passed but which
+     * the sweep has not reached yet is no longer snoozed, and counting the
+     * label would keep it in the total for up to a minute. Only used to decide
+     * whether the sidebar shows the entry at all.
+     */
+    public function countSnoozedForUser(UserInterface $user): int
+    {
+        return (int) $this->createQueryBuilder('t')
+            ->select('COUNT(t.id)')
+            ->join('t.account', 'a')
+            ->where('a.usr = :user')
+            ->andWhere('a.isActive = true')
+            ->andWhere('t.snoozedUntil IS NOT NULL')
+            ->andWhere('t.snoozedUntil > :now')
+            ->setParameter('user', $user)
+            ->setParameter('now', new \DateTimeImmutable())
+            ->getQuery()
+            ->getSingleScalarResult();
+    }
+
+    /**
+     * Snoozed conversations whose wake time has passed.
+     *
+     * Ordered oldest-first so a backlog drains in the order the user asked
+     * for, and capped so one enormous backlog cannot hold the worker.
+     *
+     * @return list<MessageThread>
+     */
+    public function findDueSnoozed(\DateTimeImmutable $now, int $limit): array
+    {
+        return $this->createQueryBuilder('t')
+            ->addSelect('m')
+            ->leftJoin('t.messages', 'm')
+            ->where('t.snoozedUntil IS NOT NULL')
+            ->andWhere('t.snoozedUntil <= :now')
+            ->setParameter('now', $now)
+            ->orderBy('t.snoozedUntil', 'ASC')
+            ->setMaxResults($limit)
+            ->getQuery()
+            ->getResult();
+    }
+
     /**
      * JMAP Thread/get: fetch by id, scoped to the account. Messages are
      * eager-joined because a Thread object is nothing but its email id list.

src/Service/Mail/ThreadSnoozeService.php

@@ -0,0 +1,167 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Service\Mail;
+
+use App\Domain\Enum\Mail\LabelRole;
+use App\Domain\Enum\Mail\MessageFlag;
+use App\Entity\Mail\MessageThread;
+use App\Jmap\State\JmapObjectType;
+use App\Jmap\State\StateManager;
+use App\Repository\Label\LabelRepository;
+use App\Service\Label\LabelChangePropagator;
+use App\Service\Label\LabelResolver;
+use App\Service\Label\ThreadLabelSynchronizer;
+use Doctrine\ORM\EntityManagerInterface;
+
+/**
+ * Snoozing a conversation, and bringing it back.
+ *
+ * Snooze is archive-with-a-timer: the thread leaves the Inbox now and returns
+ * to it later. Expressed in labels like everything else — Inbox off, Snoozed
+ * on — so the "a message carries at least one label" invariant holds without a
+ * second mechanism, and so the snoozed pile is reachable by every path that
+ * already works on labels: the sidebar, a query, the unified feed.
+ *
+ * The label change **propagates outward**, exactly as archiving does. That is
+ * the point rather than a side effect: a snoozed conversation should be out of
+ * the way in Gmail's inbox too, not just in plMail's view of it.
+ *
+ * One service rather than one implementation per caller. The JMAP method and
+ * the web UI both go through here, because a snooze that meant something
+ * different depending on which client did it is worse than no snooze.
+ */
+final class ThreadSnoozeService
+{
+    public function __construct(
+        private readonly EntityManagerInterface $entityManager,
+        private readonly LabelRepository $labelRepository,
+        private readonly LabelResolver $labelResolver,
+        private readonly ThreadLabelSynchronizer $threadLabelSynchronizer,
+        private readonly LabelChangePropagator $propagator,
+        private readonly StateManager $stateManager,
+    ) {
+    }
+
+    /**
+     * Puts a conversation away until `$until`.
+     *
+     * A time already in the past is not rejected: it simply means the next
+     * sweep wakes it, which is a harmless way to express "bring this back
+     * now" and saves callers a clock comparison.
+     */
+    public function snooze(MessageThread $thread, \DateTimeImmutable $until): void
+    {
+        $messages = $thread->getMessages()->toArray();
+
+        if ([] === $messages) {
+            return;
+        }
+
+        $account = $messages[0]->getAccount();
+        $inbox = $this->labelRepository->findOneByRoleForUser(LabelRole::Inbox, $account->getUsr());
+        $snoozed = $this->labelResolver->systemLabel(LabelRole::Snoozed, $account);
+
+        // Before the labels move, so an IMAP job still sees the source folder.
+        // Archiving is what snoozing does to the provider; the difference is
+        // only that plMail remembers to undo it.
+        $this->propagator->archive($messages);
+        $this->propagator->attachLabel($messages, $snoozed);
+
+        foreach ($messages as $message) {
+            if (null !== $inbox) {
+                $message->removeLabel($inbox);
+            }
+
+            $message->addLabel($snoozed);
+        }
+
+        $thread->setSnoozedUntil($until);
+
+        $this->finish($thread, $messages);
+    }
+
+    /**
+     * Brings a conversation back to the Inbox and clears its snooze.
+     *
+     * Marks it unread, which is the whole point: a thread that returns in the
+     * state you left it in is one you have already learned to scroll past. The
+     * read state it had is genuinely lost — that is a deliberate trade, not an
+     * oversight.
+     *
+     * Safe to call on a thread that is not snoozed; it then only ensures the
+     * Inbox label, which is what a caller racing the sweep wants anyway.
+     */
+    public function wake(MessageThread $thread): void
+    {
+        $messages = $thread->getMessages()->toArray();
+
+        if ([] === $messages) {
+            $thread->setSnoozedUntil(null);
+
+            return;
+        }
+
+        $account = $messages[0]->getAccount();
+        $inbox = $this->labelResolver->systemLabel(LabelRole::Inbox, $account);
+        $snoozed = $this->labelRepository->findOneByRoleForUser(
+            LabelRole::Snoozed,
+            $account->getUsr(),
+        );
+
+        $inboxMailbox = $inbox->bindingFor($account)?->mailbox;
+        $unread = 0;
+
+        foreach ($messages as $message) {
+            $message->addLabel($inbox);
+
+            if (null !== $snoozed) {
+                $message->removeLabel($snoozed);
+            }
+
+            // Plain-IMAP: the message physically comes back to INBOX.
+            if (null !== $message->getImapUid() && null !== $inboxMailbox) {
+                $message->setMailbox($inboxMailbox);
+            }
+
+            $message->removeFlag(MessageFlag::SEEN)->setSeenAt(null);
+            ++$unread;
+        }
+
+        $thread->setUnreadCount($unread);
+        $thread->setSnoozedUntil(null);
+
+        if (null !== $snoozed) {
+            $this->propagator->detachLabel($messages, $snoozed);
+        }
+
+        $this->propagator->attachLabel($messages, $inbox);
+        $this->propagator->markRead($messages, false);
+
+        $this->finish($thread, $messages);
+    }
+
+    /**
+     * @param list<\App\Entity\Mail\Message> $messages
+     */
+    private function finish(MessageThread $thread, array $messages): void
+    {
+        $this->threadLabelSynchronizer->sync($thread);
+
+        foreach ($messages as $message) {
+            $this->stateManager->recordUpdated(
+                (int) $message->getAccount()->getId(),
+                JmapObjectType::Email,
+                (string) $message->getId(),
+            );
+        }
+
+        $this->stateManager->recordThreadsTouched(
+            (int) $messages[0]->getAccount()->getId(),
+            [(string) $thread->getId()],
+        );
+
+        $this->entityManager->flush();
+    }
+}

src/Twig/SidebarCounts.php

@@ -24,6 +24,7 @@ class SidebarCounts
     private ?array $roleCounts = null;
     private ?array $labelCounts = null;
     private ?int $starredCount = null;
+    private ?int $snoozedCount = null;
     private ?array $userLabelTree = null;
     private ?array $visibleLabels = null;
 
@@ -122,6 +123,27 @@ class SidebarCounts
         return $children;
     }
 
+    /**
+     * True when anything is currently snoozed — controls the Snoozed entry in
+     * the system nav block.
+     *
+     * Gated rather than always shown, on the same reasoning as Archive: the
+     * label is created lazily the first time something is snoozed, so on an
+     * install that has never used the feature there is nothing to link to.
+     */
+    public function hasSnoozed(): bool
+    {
+        if (null === $this->snoozedCount) {
+            $user = $this->security->getUser();
+
+            $this->snoozedCount = null === $user
+                ? 0
+                : $this->threadRepository->countSnoozedForUser($user);
+        }
+
+        return $this->snoozedCount > 0;
+    }
+
     /**
      * True when the user's Archive label is switched visible — controls the
      * Archive entry in the system nav block.

templates/_partials/_list_toolbar.html.twig

@@ -209,7 +209,16 @@ The button itself carries `group` and `relative`.
         {{ m.tbtn('click->mail--list-toolbar#deleteSelected',     'fa-solid fa-trash',         'toolbar.actions.delete'|trans,   'hover:text-danger') }}
         {{ m.tbtn('click->mail--list-toolbar#markReadSelected',   'fa-solid fa-envelope-open', 'toolbar.actions.mark_read'|trans) }}
         {{ m.tbtn('click->mail--list-toolbar#markUnreadSelected', 'fa-solid fa-envelope',      'toolbar.actions.mark_unread'|trans) }}
-        {{ m.tbtn('click->mail--list-toolbar#snoozeSelected',     'fa-solid fa-clock',         'toolbar.actions.snooze'|trans) }}
+        {# A menu, not a direct action: this used to hardcode "tomorrow 8am"
+           with a comment asking for a picker. #}
+        <div class="relative" data-controller="ui--dropdown">
+            {{ m.tbtn('click->ui--dropdown#toggle', 'fa-solid fa-clock', 'toolbar.actions.snooze'|trans) }}
+            {% include '_partials/_snooze_menu.html.twig' with {
+                controller: 'mail--list-toolbar',
+                method:     'snoozeSelected',
+                snoozed:    false,
+            } only %}
+        </div>
         {% include '_partials/_label_menu.html.twig' with {
             labels: sidebarCounts.flattenedUserLabels,
             targetType: 'thread',

templates/_partials/_sidebar.html.twig

@@ -186,6 +186,19 @@ the layout.
             </span>
             {{ macros.unread_badge(sidebarCounts.forRole(enum('App\\Domain\\Enum\\Mail\\LabelRole').Drafts), 'role:drafts') }}
         </a>
+        {% if sidebarCounts.hasSnoozed %}
+            <a href="{{ path('app_mail_snoozed') }}"
+               class="nav-item flex items-center justify-between gap-2 px-3 py-2 rounded-lg transition-colors"
+               data-ui--sidebar-target="link"
+               data-action="{{ _drawerClose }}"
+               title="{{ 'sidebar.nav.snoozed'|trans }}">
+                <span class="flex items-center gap-2">
+                    <i class="fa-solid fa-clock w-4" aria-hidden="true"></i>
+                    <span class="rail-hide">{{ 'sidebar.nav.snoozed'|trans }}</span>
+                </span>
+                {{ macros.unread_badge(sidebarCounts.forRole(enum('App\\Domain\\Enum\\Mail\\LabelRole').Snoozed), 'role:snoozed') }}
+            </a>
+        {% endif %}
         {% if sidebarCounts.hasVisibleArchive %}
             <a href="{{ path('app_mail_archive') }}"
                class="nav-item flex items-center justify-between gap-2 px-3 py-2 rounded-lg transition-colors"

templates/_partials/_snooze_menu.html.twig

@@ -0,0 +1,58 @@
+{#
+    The snooze menu.
+
+    Labels come from here because they are translated; the wake times are filled
+    in by mail--snooze-menu once the page is running, because only the browser
+    knows what timezone "tomorrow morning" is in. Each option therefore carries a
+    data-snooze-key rather than a value, and the controller matches on it.
+
+    Parameters:
+      controller — the Stimulus identifier handling the click, e.g.
+                   "mail--message-row". Used for both the action and the
+                   namespaced url param.
+      method     — the action method on it, e.g. "snooze"
+      url        — optional endpoint for the url param; the toolbar omits it and
+                   derives per-row URLs itself
+      snoozed    — whether the target is currently snoozed, which is the only
+                   thing that puts "Unsnooze" on the menu
+#}
+{% set snoozed = snoozed|default(false) %}
+{% set url = url|default(null) %}
+{% set fire = 'click->' ~ controller ~ '#' ~ method ~ ' click->ui--dropdown#close' %}
+
+<div data-ui--dropdown-target="menu" hidden
+     data-controller="mail--snooze-menu"
+     data-action="ui--dropdown:opened->mail--snooze-menu#refresh"
+     class="absolute top-full mt-1 right-0 z-20 min-w-56 popover py-1">
+
+    <p class="px-3 py-1 text-[10px] font-semibold uppercase tracking-wide text-ink-faint">
+        {{ 'thread_row.actions.snooze'|trans }}
+    </p>
+
+    {% for key in ['later_today', 'tomorrow', 'this_weekend', 'next_week'] %}
+        <button type="button"
+                hidden
+                data-mail--snooze-menu-target="option"
+                data-snooze-key="{{ key }}"
+                {% if url %}data-{{ controller }}-snooze-url-param="{{ url }}"{% endif %}
+                data-action="{{ fire }}"
+                class="w-full flex items-center justify-between gap-3 px-3 py-2 text-sm text-ink-muted
+                       hover:bg-hover hover:text-ink transition-colors text-left">
+            <span>{{ ('snooze.' ~ key)|trans }}</span>
+            <span data-snooze-when class="text-xs text-ink-faint tabular-nums"></span>
+        </button>
+    {% endfor %}
+
+    {% if snoozed %}
+        <div class="my-1 border-t border-line"></div>
+        {# No until param at all: its absence is what clears the snooze. #}
+        <button type="button"
+                {% if url %}data-{{ controller }}-snooze-url-param="{{ url }}"{% endif %}
+                data-action="{{ fire }}"
+                class="w-full flex items-center gap-2.5 px-3 py-2 text-sm text-ink-muted
+                       hover:bg-hover hover:text-ink transition-colors text-left">
+            <i class="fa-solid fa-arrow-rotate-left w-4 text-center" aria-hidden="true"></i>
+            <span>{{ 'snooze.unsnooze'|trans }}</span>
+        </button>
+    {% endif %}
+</div>

templates/_partials/_thread_row.html.twig

@@ -194,13 +194,26 @@ the conversation it answers.
                 </button>
 
                 {% if false == draft %}
-                    <button type="button" data-action="click->mail--message-row#snooze"
-                            data-mail--message-row-snooze-url-param="{{ path('app_status_snooze', {'type': type, 'id': rowId}) }}"
-                            aria-label="{{ 'thread_row.actions.snooze'|trans }}"
-                            title="{{ 'thread_row.actions.snooze'|trans }}"
-                            class="z-10 p-1.5 cursor-pointer rounded-lg text-gray-400 hover:text-gray-700 dark:hover:text-gray-200 hover:bg-gray-200 dark:hover:bg-gray-700 transition-colors">
-                        <i class="fa-solid fa-clock w-4 h-4" aria-hidden="true"></i>
-                    </button>
+                    {# The button opens a menu rather than snoozing directly:
+                       there is no defensible default wake time, and the one
+                       this had (none at all) cleared the snooze instead of
+                       setting it. #}
+                    <div class="relative z-10" data-controller="ui--dropdown">
+                        <button type="button"
+                                data-action="click->ui--dropdown#toggle click->mail--message-row#stop"
+                                aria-label="{{ 'thread_row.actions.snooze'|trans }}"
+                                title="{{ 'thread_row.actions.snooze'|trans }}"
+                                class="p-1.5 cursor-pointer rounded-lg text-gray-400 hover:text-gray-700 dark:hover:text-gray-200 hover:bg-gray-200 dark:hover:bg-gray-700 transition-colors">
+                            <i class="fa-solid fa-clock w-4 h-4" aria-hidden="true"></i>
+                        </button>
+
+                        {% include '_partials/_snooze_menu.html.twig' with {
+                            controller: 'mail--message-row',
+                            method:     'snooze',
+                            url:        path('app_status_snooze', {'type': type, 'id': rowId}),
+                            snoozed:    thread is defined and thread.snoozed|default(false),
+                        } only %}
+                    </div>
 
                     <button type="button" data-action="click->mail--message-row#markRead"
                             data-mail--message-row-read-url-param="{{ path('app_status_mark_read', {'type': type, 'id': rowId}) }}"

templates/mail/snoozed.html.twig

@@ -0,0 +1,20 @@
+{# mail/snoozed.html.twig #}
+{% extends "_layout/_mailbox.html.twig" %}
+
+{% block list_scope %}snoozed{% endblock %}
+
+{% block title %}{{ "sidebar.nav.snoozed"|trans }} — {{ "app.name"|trans }}{% endblock %}
+
+{% block message_list %}
+    {% if threads is empty %}
+        <li class="px-4 py-8 text-center text-sm text-ink-faint">
+            {{ "snoozed.empty"|trans }}
+        </li>
+    {% else %}
+        {% for thread in threads %}
+            {% include "_partials/_thread_row.html.twig" with {
+                thread: thread,
+            } %}
+        {% endfor %}
+    {% endif %}
+{% endblock %}

tests/Command/WakeSnoozedCommandTest.php

@@ -0,0 +1,221 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Tests\Command;
+
+use App\Domain\Enum\Mail\LabelRole;
+use App\Domain\Enum\Mail\ThreadingMethod;
+use App\Entity\Mail\Account;
+use App\Entity\Mail\Mailbox;
+use App\Entity\Mail\Message;
+use App\Entity\Mail\MessageThread;
+use App\Entity\User\User;
+use App\Service\Label\LabelResolver;
+use App\Service\Mail\ThreadSnoozeService;
+use Doctrine\DBAL\Connection;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Bundle\FrameworkBundle\Console\Application;
+use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;
+use Symfony\Component\Console\Tester\CommandTester;
+
+/**
+ * The sweep is what makes a snooze a snooze.
+ *
+ * Without it a snoozed conversation leaves the inbox and never comes back,
+ * which is strictly worse than not offering the feature — the mail is not lost
+ * but the user has no reason to expect it anywhere. The scheduler runs this
+ * every minute; these tests cover what it does when it fires.
+ */
+final class WakeSnoozedCommandTest extends KernelTestCase
+{
+    private EntityManagerInterface $em;
+    private Connection $connection;
+    private LabelResolver $labelResolver;
+    private ThreadSnoozeService $snoozeService;
+    private CommandTester $command;
+
+    private Account $account;
+    private Mailbox $mailbox;
+
+    protected function setUp(): void
+    {
+        self::bootKernel();
+
+        $container = self::getContainer();
+        $this->em            = $container->get(EntityManagerInterface::class);
+        $this->connection    = $container->get(Connection::class);
+        $this->labelResolver = $container->get(LabelResolver::class);
+        $this->snoozeService = $container->get(ThreadSnoozeService::class);
+
+        $this->connection->beginTransaction();
+
+        $this->account = $this->seedAccount();
+        $this->mailbox = $this->seedMailbox();
+
+        $this->command = new CommandTester(
+            new Application(self::$kernel)->find('app:mail:wake-snoozed'),
+        );
+    }
+
+    protected function tearDown(): void
+    {
+        if (true === $this->connection->isTransactionActive()) {
+            $this->connection->rollBack();
+        }
+
+        parent::tearDown();
+    }
+
+    public function testAThreadWhoseTimeHasPassedComesBack(): void
+    {
+        $thread = $this->snoozedThread('-5 minutes');
+
+        $this->command->execute([]);
+
+        self::assertSame(0, $this->command->getStatusCode());
+        self::assertStringContainsString('Woke 1', $this->command->getDisplay());
+
+        self::assertNull($thread->getSnoozedUntil());
+        self::assertContains(LabelRole::Inbox, $this->rolesOn($thread));
+    }
+
+    /** The whole point of a wake time: before it, nothing happens. */
+    public function testAThreadStillInTheFutureIsLeftAlone(): void
+    {
+        $thread = $this->snoozedThread('+2 days');
+
+        $this->command->execute([]);
+
+        self::assertNotNull($thread->getSnoozedUntil());
+        self::assertNotContains(LabelRole::Inbox, $this->rolesOn($thread));
+    }
+
+    /**
+     * The scheduler replays a missed run when a worker comes back up, so a
+     * second sweep over the same threads must be a no-op rather than a second
+     * round of label churn and provider calls.
+     */
+    public function testASecondSweepDoesNothing(): void
+    {
+        $thread = $this->snoozedThread('-5 minutes');
+
+        $this->command->execute([]);
+        $this->command->execute([]);
+
+        // Silence, not "Woke 0": with nothing due the command returns before
+        // it writes anything, which is what keeps a once-a-minute sweep out of
+        // the logs.
+        self::assertSame('', $this->command->getDisplay());
+        self::assertSame(0, $this->command->getStatusCode());
+        self::assertNull($thread->getSnoozedUntil());
+    }
+
+    /** Nothing due is the normal case, and must stay quiet and successful. */
+    public function testAnEmptySweepSucceeds(): void
+    {
+        $this->command->execute([]);
+
+        self::assertSame(0, $this->command->getStatusCode());
+    }
+
+    // ── Fixtures ──────────────────────────────────────────────────────────
+
+    /** @return list<LabelRole|null> */
+    private function rolesOn(MessageThread $thread): array
+    {
+        $roles = [];
+
+        foreach ($thread->getMessages() as $message) {
+            foreach ($message->getLabels() as $label) {
+                $roles[] = $label->role;
+            }
+        }
+
+        return $roles;
+    }
+
+    private function snoozedThread(string $when): MessageThread
+    {
+        $thread = new MessageThread();
+        $thread
+            ->setAccount($this->account)
+            ->setSubject('Wake fixture')
+            ->setNormalizedSubject('wake fixture')
+            ->setLastMessageAt(new \DateTimeImmutable('-1 hour'))
+            ->setThreadingMethod(ThreadingMethod::References)
+            ->setUnreadCount(0);
+        $this->em->persist($thread);
+
+        $message = new Message();
+        $message
+            ->setAccount($this->account)
+            ->setSubject('Wake fixture')
+            ->setFromAddress('sender@example.test')
+            ->setReceivedAt(new \DateTimeImmutable('-1 hour'))
+            ->setHasAttachments(false)
+            ->setMessageId(sprintf('<wake-%s@example.test>', uniqid('', true)))
+            ->setMailbox($this->mailbox)
+            ->setImapUid(7000)
+            ->addLabel($this->labelResolver->systemLabel(LabelRole::Inbox, $this->account));
+
+        $thread->addMessage($message);
+        $this->em->persist($message);
+        $this->em->flush();
+
+        // Through the service, so the fixture is in the state a real snooze
+        // leaves behind rather than one this test invented.
+        $this->snoozeService->snooze($thread, new \DateTimeImmutable($when));
+
+        return $thread;
+    }
+
+    private function seedAccount(): Account
+    {
+        $user = new User();
+        $user
+            ->setEmail('wake-' . uniqid('', true) . '@example.test')
+            ->setNameFirst('Wake')
+            ->setNameLast('Fixture')
+            ->setRoles(['ROLE_USER'])
+            ->setPassword('x');
+        $this->em->persist($user);
+
+        $account = new Account();
+        $account
+            ->setUsr($user)
+            ->setEmail('Wake Fixture')
+            ->setUsername('wake-fixture@example.test')
+            ->setImapHost('localhost')
+            ->setImapPort(993)
+            ->setImapEncryption('ssl')
+            ->setSmtpHost('localhost')
+            ->setSmtpPort(587)
+            ->setSmtpEncryption('starttls')
+            ->setPassword('x')
+            ->setAuthType('password')
+            ->setIsActive(true);
+        $this->em->persist($account);
+        $this->em->flush();
+
+        return $account;
+    }
+
+    private function seedMailbox(): Mailbox
+    {
+        $mailbox = new Mailbox();
+        $mailbox
+            ->setAccount($this->account)
+            ->setName('INBOX')
+            ->setFullPath('INBOX')
+            ->setIsSyncEnabled(true)
+            ->setIsIdleEnabled(false)
+            ->setCreatedAt(new \DateTimeImmutable())
+            ->setUpdatedAt(new \DateTimeImmutable());
+
+        $this->em->persist($mailbox);
+        $this->em->flush();
+
+        return $mailbox;
+    }
+}

tests/Controller/ThreadSnoozeEndpointTest.php

@@ -0,0 +1,240 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Tests\Controller;
+
+use App\Domain\Enum\Mail\LabelRole;
+use App\Domain\Enum\Mail\ThreadingMethod;
+use App\Entity\Mail\Account;
+use App\Entity\Mail\Mailbox;
+use App\Entity\Mail\Message;
+use App\Entity\Mail\MessageThread;
+use App\Entity\User\User;
+use App\Service\Label\LabelResolver;
+use Doctrine\DBAL\Connection;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Bundle\FrameworkBundle\KernelBrowser;
+use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
+
+/**
+ * The web snooze endpoint has to mean the same thing as Thread/set.
+ *
+ * It did not. `POST /status/thread/{id}/snooze` wrote snoozedUntil and nothing
+ * else — no labels moved, nothing propagated — so the conversation stayed in
+ * the Inbox locally and at the provider while its row vanished from the list,
+ * until the sweep "woke" a thread that had never left. Both callers now go
+ * through ThreadSnoozeService, and this pins the endpoint to that.
+ *
+ * Deliberately asserted on labels rather than on the column: the column was
+ * always written correctly, and a test that checked it would have passed
+ * against the broken implementation.
+ */
+final class ThreadSnoozeEndpointTest extends WebTestCase
+{
+    private EntityManagerInterface $em;
+    private Connection $connection;
+    private LabelResolver $labelResolver;
+    private Account $account;
+
+    protected function tearDown(): void
+    {
+        if (isset($this->connection) && true === $this->connection->isTransactionActive()) {
+            $this->connection->rollBack();
+        }
+
+        parent::tearDown();
+    }
+
+    public function testSnoozingMovesTheThreadOutOfTheInbox(): void
+    {
+        $client   = $this->signIn();
+        $threadId = (int) $this->inboxThread()->getId();
+
+        $client->request(
+            'POST',
+            sprintf('/status/thread/%d/snooze', $threadId),
+            server: ['CONTENT_TYPE' => 'application/json'],
+            content: json_encode(['until' => (new \DateTimeImmutable('+1 day'))->format(DATE_ATOM)]),
+        );
+
+        self::assertResponseIsSuccessful();
+
+        $thread = $this->reload($threadId);
+
+        // Looked up, never created: systemLabel() would mint a Snoozed label
+        // as a side effect of asserting, so a broken endpoint would fail here
+        // on fixture mechanics instead of on the thing being tested.
+        $roles = [];
+
+        foreach ($thread->getMessages() as $message) {
+            foreach ($message->getLabels() as $label) {
+                $roles[] = $label->role;
+            }
+        }
+
+        self::assertNotContains(
+            LabelRole::Inbox,
+            $roles,
+            'the endpoint wrote the column but left the thread in the inbox',
+        );
+        self::assertContains(
+            LabelRole::Snoozed,
+            $roles,
+            'the endpoint wrote the column but never applied the Snoozed label',
+        );
+
+        self::assertNotNull($thread->getSnoozedUntil());
+    }
+
+    public function testSendingNoUntilClearsTheSnoozeAndRestoresTheInbox(): void
+    {
+        $client   = $this->signIn();
+        $threadId = (int) $this->inboxThread()->getId();
+        $path     = sprintf('/status/thread/%d/snooze', $threadId);
+
+        $client->request(
+            'POST',
+            $path,
+            server: ['CONTENT_TYPE' => 'application/json'],
+            content: json_encode(['until' => (new \DateTimeImmutable('+1 day'))->format(DATE_ATOM)]),
+        );
+
+        $client->request(
+            'POST',
+            $path,
+            server: ['CONTENT_TYPE' => 'application/json'],
+            content: json_encode(['until' => null]),
+        );
+
+        self::assertResponseIsSuccessful();
+
+        $thread = $this->reload($threadId);
+        $roles  = [];
+
+        foreach ($thread->getMessages()->first()->getLabels() as $label) {
+            $roles[] = $label->role;
+        }
+
+        self::assertNull($thread->getSnoozedUntil());
+        self::assertContains(LabelRole::Inbox, $roles);
+        self::assertNotContains(LabelRole::Snoozed, $roles);
+    }
+
+    // ── Fixtures ──────────────────────────────────────────────────────────
+
+    /**
+     * Re-read the thread from the container's current EntityManager.
+     *
+     * By id rather than refresh(): the kernel is rebooted between requests, so
+     * the instance the fixtures returned is detached by the time the
+     * assertions run and refresh() would reject it.
+     */
+    private function reload(int $id): MessageThread
+    {
+        $em = static::getContainer()->get(EntityManagerInterface::class);
+        $em->clear();
+
+        $thread = $em->find(MessageThread::class, $id);
+
+        self::assertNotNull($thread, 'thread vanished');
+
+        return $thread;
+    }
+
+    private function signIn(): KernelBrowser
+    {
+        $client = static::createClient();
+
+        // One kernel across the whole test. The client reboots between
+        // requests by default, which detaches the EntityManager this test
+        // holds — and the unsnooze case needs two requests against the same
+        // fixtures.
+        $client->disableReboot();
+
+        $container = static::getContainer();
+        $this->em            = $container->get(EntityManagerInterface::class);
+        $this->connection    = $container->get(Connection::class);
+        $this->labelResolver = $container->get(LabelResolver::class);
+
+        // Rolled back in tearDown. Without it this test commits an Account
+        // onto a shared user, and AccountFormControllersTest — which renders
+        // the onboarding account step — starts seeing a different page.
+        $this->connection->beginTransaction();
+
+        // Its own user rather than the seeded admin, for the same reason: the
+        // fixtures here change what onboarding thinks the account holds.
+        $user = new User();
+        $user
+            ->setEmail('snooze-endpoint-' . uniqid('', true) . '@example.test')
+            ->setNameFirst('Snooze')
+            ->setNameLast('Endpoint')
+            ->setRoles(['ROLE_USER'])
+            ->setPassword('x');
+        $this->em->persist($user);
+        $this->em->flush();
+
+        $client->loginUser($user);
+
+        $this->account = new Account();
+        $this->account
+            ->setUsr($user)
+            ->setEmail('Snooze Endpoint')
+            ->setUsername('snooze-endpoint-' . uniqid('', true) . '@example.test')
+            ->setImapHost('localhost')
+            ->setImapPort(993)
+            ->setImapEncryption('ssl')
+            ->setSmtpHost('localhost')
+            ->setSmtpPort(587)
+            ->setSmtpEncryption('starttls')
+            ->setPassword('x')
+            ->setAuthType('password')
+            ->setIsActive(true);
+        $this->em->persist($this->account);
+        $this->em->flush();
+
+        return $client;
+    }
+
+    private function inboxThread(): MessageThread
+    {
+        $mailbox = new Mailbox();
+        $mailbox
+            ->setAccount($this->account)
+            ->setName('INBOX')
+            ->setFullPath('INBOX')
+            ->setIsSyncEnabled(true)
+            ->setIsIdleEnabled(false)
+            ->setCreatedAt(new \DateTimeImmutable())
+            ->setUpdatedAt(new \DateTimeImmutable());
+        $this->em->persist($mailbox);
+
+        $thread = new MessageThread();
+        $thread
+            ->setAccount($this->account)
+            ->setSubject('Endpoint fixture')
+            ->setNormalizedSubject('endpoint fixture')
+            ->setLastMessageAt(new \DateTimeImmutable('-1 hour'))
+            ->setThreadingMethod(ThreadingMethod::References)
+            ->setUnreadCount(0);
+        $this->em->persist($thread);
+
+        $message = new Message();
+        $message
+            ->setAccount($this->account)
+            ->setSubject('Endpoint fixture')
+            ->setFromAddress('sender@example.test')
+            ->setReceivedAt(new \DateTimeImmutable('-1 hour'))
+            ->setHasAttachments(false)
+            ->setMessageId(sprintf('<snooze-endpoint-%s@example.test>', uniqid('', true)))
+            ->setMailbox($mailbox)
+            ->setImapUid(4242)
+            ->addLabel($this->labelResolver->systemLabel(LabelRole::Inbox, $this->account));
+
+        $thread->addMessage($message);
+        $this->em->persist($message);
+        $this->em->flush();
+
+        return $thread;
+    }
+}

tests/Jmap/Method/ThreadSetMethodTest.php

@@ -0,0 +1,279 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Tests\Jmap\Method;
+
+use App\Domain\Enum\Mail\LabelRole;
+use App\Domain\Enum\Mail\ThreadingMethod;
+use App\Entity\Mail\Account;
+use App\Entity\Mail\Mailbox;
+use App\Entity\Mail\Message;
+use App\Entity\Mail\MessageThread;
+use App\Entity\User\User;
+use App\Jmap\Method\Mail\ThreadSetMethod;
+use App\Jmap\Protocol\Exception\MethodException;
+use App\Jmap\Protocol\JmapContext;
+use App\Service\Label\LabelResolver;
+use Doctrine\DBAL\Connection;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;
+
+/**
+ * "Thread/set" is a plMail extension, so its shape is ours to get right.
+ *
+ * RFC 8621's Thread is read-only. This adds exactly one settable property, and
+ * the tests below are mostly about what it refuses: a method that accepted
+ * `create`, or silently ignored an unknown property, would be inventing
+ * semantics the rest of the system has no meaning for.
+ *
+ * The snooze behaviour itself lives in ThreadSnoozeServiceTest — here the
+ * question is only whether the method routes to it.
+ */
+final class ThreadSetMethodTest extends KernelTestCase
+{
+    private EntityManagerInterface $em;
+    private Connection $connection;
+    private LabelResolver $labelResolver;
+    private ThreadSetMethod $method;
+
+    private User $user;
+    private Account $account;
+    private Mailbox $mailbox;
+
+    protected function setUp(): void
+    {
+        self::bootKernel();
+
+        $container = self::getContainer();
+        $this->em            = $container->get(EntityManagerInterface::class);
+        $this->connection    = $container->get(Connection::class);
+        $this->labelResolver = $container->get(LabelResolver::class);
+        $this->method        = $container->get(ThreadSetMethod::class);
+
+        $this->connection->beginTransaction();
+
+        $this->seed();
+    }
+
+    protected function tearDown(): void
+    {
+        if (true === $this->connection->isTransactionActive()) {
+            $this->connection->rollBack();
+        }
+
+        parent::tearDown();
+    }
+
+    public function testItIsNamedThreadSet(): void
+    {
+        self::assertSame('Thread/set', $this->method->name());
+    }
+
+    public function testSettingSnoozedUntilSnoozesTheThread(): void
+    {
+        $thread = $this->inboxThread();
+
+        $result = $this->handle([
+            'update' => [
+                (string) $thread->getId() => [
+                    'snoozedUntil' => (new \DateTimeImmutable('+1 day'))->format('Y-m-d\TH:i:s\Z'),
+                ],
+            ],
+        ]);
+
+        self::assertArrayHasKey((string) $thread->getId(), (array) $result['updated']);
+        self::assertNotNull($thread->getSnoozedUntil());
+        self::assertNotContains(LabelRole::Inbox, $this->rolesOn($thread));
+    }
+
+    public function testNullClearsTheSnooze(): void
+    {
+        $thread = $this->inboxThread();
+        $id     = (string) $thread->getId();
+
+        $this->handle([
+            'update' => [$id => ['snoozedUntil' => (new \DateTimeImmutable('+1 day'))->format('Y-m-d\TH:i:s\Z')]],
+        ]);
+
+        $this->handle(['update' => [$id => ['snoozedUntil' => null]]]);
+
+        self::assertNull($thread->getSnoozedUntil());
+        self::assertContains(LabelRole::Inbox, $this->rolesOn($thread));
+    }
+
+    /**
+     * Threads come into being by mail arriving. A client that could conjure one
+     * would be describing something nothing else in the system understands.
+     */
+    public function testCreateIsRefused(): void
+    {
+        $this->expectException(MethodException::class);
+
+        $this->handle(['create' => ['tmp' => ['snoozedUntil' => null]]]);
+    }
+
+    public function testDestroyIsRefused(): void
+    {
+        $this->expectException(MethodException::class);
+
+        $this->handle(['destroy' => ['1']]);
+    }
+
+    /**
+     * Refused rather than ignored: a client told its write succeeded, when the
+     * property was silently dropped, has no way to discover otherwise.
+     */
+    public function testAnUnknownPropertyIsRejectedForThatThread(): void
+    {
+        $thread = $this->inboxThread();
+
+        $result = $this->handle([
+            'update' => [(string) $thread->getId() => ['subject' => 'nope']],
+        ]);
+
+        self::assertArrayHasKey((string) $thread->getId(), (array) $result['notUpdated']);
+        self::assertCount(0, (array) $result['updated']);
+    }
+
+    /**
+     * The web endpoint substitutes "in 1 day" on an unparseable date, which is
+     * defensible for a form post. For an API it is not: the client would be
+     * told it succeeded and find the thread back at a time it never chose.
+     */
+    public function testAMalformedDateIsRefusedRatherThanCoerced(): void
+    {
+        $thread = $this->inboxThread();
+
+        $result = $this->handle([
+            'update' => [(string) $thread->getId() => ['snoozedUntil' => 'next tuesday-ish']],
+        ]);
+
+        self::assertArrayHasKey((string) $thread->getId(), (array) $result['notUpdated']);
+        self::assertNull($thread->getSnoozedUntil());
+    }
+
+    /** Scoped by account, so guessing an integer reaches nothing. */
+    public function testAThreadOutsideTheAccountIsNotFound(): void
+    {
+        $result = $this->handle(['update' => ['999999' => ['snoozedUntil' => null]]]);
+
+        self::assertSame('notFound', ((array) $result['notUpdated'])['999999']['type']);
+    }
+
+    /** An empty patch changes nothing, and must not be an error. */
+    public function testAnEmptyPatchIsANoOp(): void
+    {
+        $thread = $this->inboxThread();
+
+        $result = $this->handle(['update' => [(string) $thread->getId() => []]]);
+
+        self::assertArrayHasKey((string) $thread->getId(), (array) $result['updated']);
+        self::assertNull($thread->getSnoozedUntil());
+    }
+
+    // ── Helpers ───────────────────────────────────────────────────────────
+
+    /**
+     * @param array<string,mixed> $arguments
+     *
+     * @return array<string,mixed>
+     */
+    private function handle(array $arguments): array
+    {
+        return $this->method->handle(
+            $arguments + ['accountId' => (string) $this->account->getId()],
+            new JmapContext($this->user),
+        );
+    }
+
+    /** @return list<LabelRole|null> */
+    private function rolesOn(MessageThread $thread): array
+    {
+        $roles = [];
+
+        foreach ($thread->getMessages() as $message) {
+            foreach ($message->getLabels() as $label) {
+                $roles[] = $label->role;
+            }
+        }
+
+        return $roles;
+    }
+
+    private function inboxThread(): MessageThread
+    {
+        $thread = new MessageThread();
+        $thread
+            ->setAccount($this->account)
+            ->setSubject('Thread/set fixture')
+            ->setNormalizedSubject('thread/set fixture')
+            ->setLastMessageAt(new \DateTimeImmutable('-1 hour'))
+            ->setThreadingMethod(ThreadingMethod::References)
+            ->setUnreadCount(0);
+        $this->em->persist($thread);
+
+        $message = new Message();
+        $message
+            ->setAccount($this->account)
+            ->setSubject('Thread/set fixture')
+            ->setFromAddress('sender@example.test')
+            ->setReceivedAt(new \DateTimeImmutable('-1 hour'))
+            ->setHasAttachments(false)
+            ->setMessageId(sprintf('<threadset-%s@example.test>', uniqid('', true)))
+            ->setMailbox($this->mailbox)
+            ->setImapUid(8000)
+            ->addLabel($this->labelResolver->systemLabel(LabelRole::Inbox, $this->account));
+
+        $thread->addMessage($message);
+        $this->em->persist($message);
+        $this->em->flush();
+
+        return $thread;
+    }
+
+    private function seed(): void
+    {
+        $this->user = new User();
+        $this->user
+            ->setEmail('threadset-' . uniqid('', true) . '@example.test')
+            ->setNameFirst('Thread')
+            ->setNameLast('Set')
+            ->setRoles(['ROLE_USER'])
+            ->setPassword('x');
+        $this->em->persist($this->user);
+
+        $this->account = new Account();
+        $this->account
+            ->setUsr($this->user)
+            ->setEmail('Thread Set')
+            ->setUsername('threadset-fixture@example.test')
+            ->setImapHost('localhost')
+            ->setImapPort(993)
+            ->setImapEncryption('ssl')
+            ->setSmtpHost('localhost')
+            ->setSmtpPort(587)
+            ->setSmtpEncryption('starttls')
+            ->setPassword('x')
+            ->setAuthType('password')
+            ->setIsActive(true);
+        $this->em->persist($this->account);
+
+        $this->mailbox = new Mailbox();
+        $this->mailbox
+            ->setAccount($this->account)
+            ->setName('INBOX')
+            ->setFullPath('INBOX')
+            ->setIsSyncEnabled(true)
+            ->setIsIdleEnabled(false)
+            ->setCreatedAt(new \DateTimeImmutable())
+            ->setUpdatedAt(new \DateTimeImmutable());
+        $this->em->persist($this->mailbox);
+
+        $this->em->flush();
+
+        // getAccounts() is what AccountResolver scopes on, and the inverse
+        // side is not populated by persisting the owning side alone.
+        $this->user->addAccount($this->account);
+    }
+}

tests/Service/Mail/ThreadSnoozeServiceTest.php

@@ -0,0 +1,312 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Tests\Service\Mail;
+
+use App\Domain\Enum\Mail\LabelRole;
+use App\Domain\Enum\Mail\MessageFlag;
+use App\Domain\Enum\Mail\ThreadingMethod;
+use App\Entity\Mail\Account;
+use App\Entity\Mail\Mailbox;
+use App\Entity\Mail\Message;
+use App\Entity\Mail\MessageThread;
+use App\Entity\User\User;
+use App\Repository\Label\LabelRepository;
+use App\Service\Label\LabelResolver;
+use App\Service\Mail\ThreadSnoozeService;
+use Doctrine\DBAL\Connection;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;
+use Symfony\Component\Messenger\Transport\InMemory\InMemoryTransport;
+
+/**
+ * Snooze is a label move, not a column write.
+ *
+ * That distinction is the whole subject here. The web endpoint used to set
+ * snoozedUntil directly and nothing else, which left the conversation sitting
+ * in the Inbox — locally and at the provider — while the row disappeared from
+ * the list, until the sweep "woke" a thread that had never left.
+ *
+ * Against a real container and a real database rather than doubles, for two
+ * reasons. Every collaborator this service takes is `final`, so none of them
+ * can be doubled anyway; and the behaviour worth pinning is the one that
+ * emerges from them together — labels moved, an outward propagation queued —
+ * which a set of mocks would assert into existence rather than observe.
+ */
+final class ThreadSnoozeServiceTest extends KernelTestCase
+{
+    private EntityManagerInterface $em;
+    private Connection $connection;
+    private ThreadSnoozeService $service;
+    private LabelResolver $labelResolver;
+    private LabelRepository $labelRepository;
+
+    private Account $account;
+    private Mailbox $inboxMailbox;
+
+    protected function setUp(): void
+    {
+        self::bootKernel();
+
+        $container = self::getContainer();
+        $this->em              = $container->get(EntityManagerInterface::class);
+        $this->connection      = $container->get(Connection::class);
+        $this->service         = $container->get(ThreadSnoozeService::class);
+        $this->labelResolver   = $container->get(LabelResolver::class);
+        $this->labelRepository = $container->get(LabelRepository::class);
+
+        // Never committed, so the suite leaves nothing behind and can be run
+        // repeatedly against the same database.
+        $this->connection->beginTransaction();
+
+        $this->account      = $this->seedAccount();
+        $this->inboxMailbox = $this->seedMailbox();
+    }
+
+    protected function tearDown(): void
+    {
+        if (true === $this->connection->isTransactionActive()) {
+            $this->connection->rollBack();
+        }
+
+        parent::tearDown();
+    }
+
+    public function testSnoozeMovesTheThreadOutOfTheInbox(): void
+    {
+        $thread = $this->inboxThread(2);
+        $until  = new \DateTimeImmutable('+1 day');
+
+        $this->service->snooze($thread, $until);
+
+        $inbox   = $this->role(LabelRole::Inbox);
+        $snoozed = $this->role(LabelRole::Snoozed);
+
+        foreach ($thread->getMessages() as $message) {
+            self::assertFalse($message->getLabels()->contains($inbox), 'Inbox label should be gone');
+            self::assertTrue($message->getLabels()->contains($snoozed), 'Snoozed label should be set');
+        }
+
+        self::assertSame($until, $thread->getSnoozedUntil());
+        self::assertTrue($thread->isSnoozed());
+    }
+
+    /**
+     * The regression that matters most: a snooze the provider never hears about
+     * leaves the conversation in the Gmail inbox, which is exactly what
+     * snoozing is supposed to prevent. The propagator works by queueing, so the
+     * observable fact is that something was queued.
+     */
+    public function testSnoozeQueuesTheOutwardChange(): void
+    {
+        $transport = $this->transport();
+        $before    = count($transport->getSent());
+
+        $this->service->snooze($this->inboxThread(1), new \DateTimeImmutable('+1 day'));
+
+        self::assertGreaterThan(
+            $before,
+            count($transport->getSent()),
+            'snoozing must propagate outward, not only move local labels',
+        );
+    }
+
+    public function testWakeReturnsTheThreadToTheInboxAndClearsTheSnooze(): void
+    {
+        $thread = $this->inboxThread(2);
+        $this->service->snooze($thread, new \DateTimeImmutable('+1 day'));
+
+        $this->service->wake($thread);
+
+        $inbox   = $this->role(LabelRole::Inbox);
+        $snoozed = $this->role(LabelRole::Snoozed);
+
+        foreach ($thread->getMessages() as $message) {
+            self::assertTrue($message->getLabels()->contains($inbox));
+            self::assertFalse($message->getLabels()->contains($snoozed));
+        }
+
+        self::assertNull($thread->getSnoozedUntil());
+        self::assertFalse($thread->isSnoozed());
+    }
+
+    /**
+     * Waking marks unread on purpose — a thread that comes back in the state it
+     * left in is one the reader has already trained themselves to scroll past.
+     */
+    public function testWakeMarksEveryMessageUnread(): void
+    {
+        $thread = $this->inboxThread(3);
+
+        foreach ($thread->getMessages() as $message) {
+            $message->addFlag(MessageFlag::SEEN)->setSeenAt(new \DateTimeImmutable());
+        }
+
+        $this->em->flush();
+
+        $this->service->wake($thread);
+
+        foreach ($thread->getMessages() as $message) {
+            self::assertFalse($message->hasFlag(MessageFlag::SEEN));
+            self::assertNull($message->getSeenAt());
+        }
+
+        self::assertSame(3, $thread->getUnreadCount());
+    }
+
+    /**
+     * The sweep and a user clicking "unsnooze" can race, and the scheduler
+     * replays a missed run — so waking twice has to be harmless.
+     */
+    public function testWakeIsIdempotent(): void
+    {
+        $thread = $this->inboxThread(1);
+        $this->service->snooze($thread, new \DateTimeImmutable('+1 day'));
+
+        $this->service->wake($thread);
+        $this->service->wake($thread);
+
+        self::assertNull($thread->getSnoozedUntil());
+        self::assertTrue(
+            $thread->getMessages()->first()->getLabels()->contains($this->role(LabelRole::Inbox)),
+        );
+    }
+
+    /**
+     * A past time is accepted rather than rejected: it is a legitimate way to
+     * say "bring this back on the next sweep", and saves every caller a clock
+     * comparison.
+     */
+    public function testSnoozeAcceptsATimeInThePast(): void
+    {
+        $thread = $this->inboxThread(1);
+        $past   = new \DateTimeImmutable('-1 hour');
+
+        $this->service->snooze($thread, $past);
+
+        self::assertSame($past, $thread->getSnoozedUntil());
+        self::assertFalse($thread->isSnoozed(), 'already due, so not snoozed');
+    }
+
+    /** A thread with no messages has no labels to move; it must not fatal. */
+    public function testEmptyThreadIsSafe(): void
+    {
+        $thread = new MessageThread();
+        $thread
+            ->setAccount($this->account)
+            ->setSubject('Empty')
+            ->setNormalizedSubject('empty')
+            ->setLastMessageAt(new \DateTimeImmutable('-1 hour'))
+            ->setThreadingMethod(ThreadingMethod::References)
+            ->setSnoozedUntil(new \DateTimeImmutable('+1 day'));
+        $this->em->persist($thread);
+        $this->em->flush();
+
+        $this->service->snooze($thread, new \DateTimeImmutable('+2 days'));
+        $this->service->wake($thread);
+
+        self::assertNull($thread->getSnoozedUntil());
+    }
+
+    // ── Fixtures ──────────────────────────────────────────────────────────
+
+    private function role(LabelRole $role): object
+    {
+        return $this->labelResolver->systemLabel($role, $this->account);
+    }
+
+    private function inboxThread(int $messages): MessageThread
+    {
+        $inbox  = $this->role(LabelRole::Inbox);
+        $thread = new MessageThread();
+        $thread
+            ->setAccount($this->account)
+            ->setSubject('Snooze fixture')
+            ->setNormalizedSubject('snooze fixture')
+            ->setLastMessageAt(new \DateTimeImmutable('-1 hour'))
+            ->setThreadingMethod(ThreadingMethod::References)
+            ->setUnreadCount(0);
+        $this->em->persist($thread);
+
+        for ($i = 0; $i < $messages; $i++) {
+            $message = new Message();
+            $message
+                ->setAccount($this->account)
+                ->setSubject(sprintf('Snooze fixture %d', $i))
+                ->setFromAddress('sender@example.test')
+                ->setReceivedAt(new \DateTimeImmutable('-1 hour'))
+                ->setHasAttachments(false)
+                ->setMessageId(sprintf('<snooze-%s-%d@example.test>', uniqid('', true), $i))
+                // A mailbox and a UID, because LabelChangePropagator skips
+                // messages that have neither — without them the propagation
+                // assertion would be testing the fixture, not the service.
+                ->setMailbox($this->inboxMailbox)
+                ->setImapUid(1000 + $i);
+
+            $message->addLabel($inbox);
+            $thread->addMessage($message);
+
+            $this->em->persist($message);
+        }
+
+        $this->em->flush();
+
+        return $thread;
+    }
+
+    private function seedAccount(): Account
+    {
+        $user = new User();
+        $user
+            ->setEmail('snooze-' . uniqid('', true) . '@example.test')
+            ->setNameFirst('Snooze')
+            ->setNameLast('Fixture')
+            ->setRoles(['ROLE_USER'])
+            ->setPassword('x');
+        $this->em->persist($user);
+
+        $account = new Account();
+        $account
+            ->setUsr($user)
+            ->setEmail('Snooze Fixture')
+            ->setUsername('snooze-fixture@example.test')
+            ->setImapHost('localhost')
+            ->setImapPort(993)
+            ->setImapEncryption('ssl')
+            ->setSmtpHost('localhost')
+            ->setSmtpPort(587)
+            ->setSmtpEncryption('starttls')
+            ->setPassword('x')
+            ->setAuthType('password')
+            ->setIsActive(true);
+        $this->em->persist($account);
+
+        $this->em->flush();
+
+        return $account;
+    }
+
+    private function seedMailbox(): Mailbox
+    {
+        $mailbox = new Mailbox();
+        $mailbox
+            ->setAccount($this->account)
+            ->setName('INBOX')
+            ->setFullPath('INBOX')
+            ->setIsSyncEnabled(true)
+            ->setIsIdleEnabled(false)
+            ->setCreatedAt(new \DateTimeImmutable())
+            ->setUpdatedAt(new \DateTimeImmutable());
+
+        $this->em->persist($mailbox);
+        $this->em->flush();
+
+        return $mailbox;
+    }
+
+    private function transport(): InMemoryTransport
+    {
+        return self::getContainer()->get('messenger.transport.async');
+    }
+}

translations/messages.de.yaml

@@ -1088,10 +1088,24 @@ sidebar:
         drafts: Entwürfe
         inbox: Posteingang
         sent: Gesendet
+        snoozed: Zurückgestellt
         starred: Markiert
         trash: Papierkorb
     toggle: Seitenleiste ein-/ausblenden
 
+snooze:
+    later_today: Später heute
+    next_week: Nächste Woche
+    pick_date: Datum und Uhrzeit wählen
+    this_weekend: Dieses Wochenende
+    tomorrow: Morgen
+    unsnooze: Zurückholen
+
+snoozed:
+    empty: Nichts ist zurückgestellt.
+    heading: Zurückgestellt
+    until: Kommt %when% zurück
+
 starred:
     empty: Keine markierten Nachrichten.
     heading: Markiert

translations/messages.en.yaml

@@ -1069,10 +1069,24 @@ sidebar:
         drafts: Drafts
         inbox: Inbox
         sent: Sent
+        snoozed: Snoozed
         starred: Starred
         trash: Trash
     toggle: Show or hide the sidebar
 
+snooze:
+    later_today: Later today
+    next_week: Next week
+    pick_date: Pick a date and time
+    this_weekend: This weekend
+    tomorrow: Tomorrow
+    unsnooze: Unsnooze
+
+snoozed:
+    empty: Nothing is snoozed.
+    heading: Snoozed
+    until: Comes back %when%
+
 starred:
     empty: No starred messages.
     heading: Starred

translations/messages.en_PI.yaml

@@ -1064,10 +1064,24 @@ sidebar:
         drafts: Scrolls in the works
         inbox: Bottles washed ashore
         sent: Cast off
+        snoozed: Kept below deck
         starred: Marked with an X
         trash: Davy Jones' locker
     toggle: Raise or lower th' side riggin'
 
+snooze:
+    later_today: Later this watch
+    next_week: Next se'nnight
+    pick_date: Name th' day and th' hour
+    this_weekend: Come th' weekend
+    tomorrow: On th' morrow
+    unsnooze: Haul it back up
+
+snoozed:
+    empty: Naught kept below deck.
+    heading: Kept below deck
+    until: Surfaces %when%
+
 starred:
     empty: Naught marked with an X.
     heading: Marked with an X