diff --git a/src/app/features/room/msgContent.test.ts b/src/app/features/room/msgContent.test.ts
new file mode 100644
index 000000000..6656728ad
--- /dev/null
+++ b/src/app/features/room/msgContent.test.ts
@@ -0,0 +1,76 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { MsgType } from 'matrix-js-sdk';
+import { EncryptedAttachmentInfo } from 'browser-encrypt-attachment';
+import { getAudioMsgContent, getFileMsgContent } from './msgContent';
+import { TUploadItem } from '../../state/room/roomInputDrafts';
+
+// Pure builders getAudioMsgContent / getFileMsgContent: msgtype/body/filename/info
+// shape plus the encInfo branch (content.file w/ url vs plain content.url). The
+// image/video builders need a DOM + MatrixClient and are not covered here.
+
+const MXC = 'mxc://example.org/abc';
+
+const makeItem = (encInfo?: EncryptedAttachmentInfo): TUploadItem => {
+  const file = { name: 'sound.ogg', type: 'audio/ogg', size: 4096 };
+  return {
+    file,
+    originalFile: file,
+    metadata: { markedAsSpoiler: false },
+    encInfo,
+  } as unknown as TUploadItem;
+};
+
+const fakeEncInfo = (): EncryptedAttachmentInfo =>
+  ({
+    v: 'v2',
+    key: { alg: 'A256CTR' },
+    iv: 'iv',
+    hashes: { sha256: 'h' },
+  }) as unknown as EncryptedAttachmentInfo;
+
+test('getAudioMsgContent builds an unencrypted audio message', () => {
+  const content = getAudioMsgContent(makeItem(), MXC);
+  assert.equal(content.msgtype, MsgType.Audio);
+  assert.equal(content.body, 'sound.ogg');
+  assert.equal(content.filename, 'sound.ogg');
+  assert.deepEqual(content.info, { mimetype: 'audio/ogg', size: 4096 });
+  assert.equal(content.url, MXC);
+  assert.equal(content.file, undefined);
+});
+
+test('getAudioMsgContent uses content.file with url when encInfo is present', () => {
+  const enc = fakeEncInfo();
+  const content = getAudioMsgContent(makeItem(enc), MXC);
+  assert.equal(content.url, undefined);
+  assert.deepEqual(content.file, { ...enc, url: MXC });
+});
+
+test('getFileMsgContent builds an unencrypted file message', () => {
+  const content = getFileMsgContent(makeItem(), MXC);
+  assert.equal(content.msgtype, MsgType.File);
+  assert.equal(content.body, 'sound.ogg');
+  assert.equal(content.filename, 'sound.ogg');
+  assert.deepEqual(content.info, { mimetype: 'audio/ogg', size: 4096 });
+  assert.equal(content.url, MXC);
+  assert.equal(content.file, undefined);
+});
+
+test('getFileMsgContent uses content.file with url when encInfo is present', () => {
+  const enc = fakeEncInfo();
+  const content = getFileMsgContent(makeItem(enc), MXC);
+  assert.equal(content.url, undefined);
+  assert.deepEqual(content.file, { ...enc, url: MXC });
+});
+
+test('info mirrors the file mimetype and size', () => {
+  const item = {
+    file: { name: 'doc.pdf', type: 'application/pdf', size: 12 },
+    originalFile: { name: 'doc.pdf', type: 'application/pdf', size: 12 },
+    metadata: { markedAsSpoiler: false },
+    encInfo: undefined,
+  } as unknown as TUploadItem;
+  const content = getFileMsgContent(item, MXC);
+  assert.deepEqual(content.info, { mimetype: 'application/pdf', size: 12 });
+  assert.equal(content.body, 'doc.pdf');
+});
diff --git a/src/app/state/backupRestore.test.ts b/src/app/state/backupRestore.test.ts
new file mode 100644
index 000000000..3c5cb3715
--- /dev/null
+++ b/src/app/state/backupRestore.test.ts
@@ -0,0 +1,68 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { createStore } from 'jotai';
+import { ImportRoomKeyProgressData, ImportRoomKeyStage } from 'matrix-js-sdk/lib/crypto-api';
+import { backupRestoreProgressAtom, BackupProgressStatus } from './backupRestore';
+
+// backupRestoreProgressAtom maps ImportRoomKeyProgressData stages onto an
+// IBackupProgress status held in an unexported baseAtom:
+//   Fetch    -> Fetching
+//   LoadKeys with successes+failures === total -> Done
+//   LoadKeys otherwise -> Loading{ downloaded = successes+failures }
+// We drive the write atom through a jotai store and read back the getter.
+
+const load = (successes: number, failures: number, total: number): ImportRoomKeyProgressData => ({
+  stage: ImportRoomKeyStage.LoadKeys,
+  successes,
+  failures,
+  total,
+});
+
+test('starts Idle', () => {
+  const store = createStore();
+  assert.deepEqual(store.get(backupRestoreProgressAtom), {
+    status: BackupProgressStatus.Idle,
+  });
+});
+
+test('Fetch stage -> Fetching', () => {
+  const store = createStore();
+  store.set(backupRestoreProgressAtom, { stage: ImportRoomKeyStage.Fetch });
+  assert.deepEqual(store.get(backupRestoreProgressAtom), {
+    status: BackupProgressStatus.Fetching,
+  });
+});
+
+test('LoadKeys with downloaded === total -> Done', () => {
+  const store = createStore();
+  store.set(backupRestoreProgressAtom, load(8, 2, 10));
+  assert.deepEqual(store.get(backupRestoreProgressAtom), {
+    status: BackupProgressStatus.Done,
+  });
+});
+
+test('LoadKeys mid-progress -> Loading with downloaded = successes + failures', () => {
+  const store = createStore();
+  store.set(backupRestoreProgressAtom, load(3, 1, 10));
+  assert.deepEqual(store.get(backupRestoreProgressAtom), {
+    status: BackupProgressStatus.Loading,
+    data: { downloaded: 4, successes: 3, failures: 1, total: 10 },
+  });
+});
+
+test('LoadKeys at zero progress -> Loading with downloaded 0', () => {
+  const store = createStore();
+  store.set(backupRestoreProgressAtom, load(0, 0, 5));
+  assert.deepEqual(store.get(backupRestoreProgressAtom), {
+    status: BackupProgressStatus.Loading,
+    data: { downloaded: 0, successes: 0, failures: 0, total: 5 },
+  });
+});
+
+test('Fetch then LoadKeys completion transitions Fetching -> Done', () => {
+  const store = createStore();
+  store.set(backupRestoreProgressAtom, { stage: ImportRoomKeyStage.Fetch });
+  assert.equal(store.get(backupRestoreProgressAtom).status, BackupProgressStatus.Fetching);
+  store.set(backupRestoreProgressAtom, load(5, 0, 5));
+  assert.equal(store.get(backupRestoreProgressAtom).status, BackupProgressStatus.Done);
+});
diff --git a/src/app/state/callEmbed.test.ts b/src/app/state/callEmbed.test.ts
new file mode 100644
index 000000000..a624c3236
--- /dev/null
+++ b/src/app/state/callEmbed.test.ts
@@ -0,0 +1,80 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { createStore } from 'jotai';
+import { callEmbedAtom } from './callEmbed';
+import { CallEmbed } from '../plugins/call';
+
+// callEmbedAtom holds the current CallEmbed in an unexported baseAtom. The setter:
+//   - identity no-op guard: setting the same reference does nothing
+//   - when replacing a previous embed, calls prevCallEmbed.dispose()
+// We substitute a stub embed exposing a dispose() spy (the real CallEmbed needs a
+// MatrixClient + DOM). `as unknown as CallEmbed` keeps eslint/prettier quiet.
+
+type StubEmbed = { dispose: () => void; disposed: number };
+
+const makeEmbed = (): StubEmbed => {
+  const stub: StubEmbed = {
+    disposed: 0,
+    dispose() {
+      stub.disposed += 1;
+    },
+  };
+  return stub;
+};
+
+const asEmbed = (e: StubEmbed): CallEmbed => e as unknown as CallEmbed;
+
+test('starts undefined', () => {
+  const store = createStore();
+  assert.equal(store.get(callEmbedAtom), undefined);
+});
+
+test('sets a call embed', () => {
+  const store = createStore();
+  const embed = makeEmbed();
+  store.set(callEmbedAtom, asEmbed(embed));
+  assert.equal(store.get(callEmbedAtom), asEmbed(embed));
+  assert.equal(embed.disposed, 0);
+});
+
+test('replacing an embed disposes the previous one', () => {
+  const store = createStore();
+  const first = makeEmbed();
+  const second = makeEmbed();
+
+  store.set(callEmbedAtom, asEmbed(first));
+  store.set(callEmbedAtom, asEmbed(second));
+
+  assert.equal(first.disposed, 1);
+  assert.equal(second.disposed, 0);
+  assert.equal(store.get(callEmbedAtom), asEmbed(second));
+});
+
+test('setting the same embed reference is a no-op (no dispose)', () => {
+  const store = createStore();
+  const embed = makeEmbed();
+
+  store.set(callEmbedAtom, asEmbed(embed));
+  store.set(callEmbedAtom, asEmbed(embed));
+
+  assert.equal(embed.disposed, 0);
+  assert.equal(store.get(callEmbedAtom), asEmbed(embed));
+});
+
+test('clearing to undefined disposes the previous embed', () => {
+  const store = createStore();
+  const embed = makeEmbed();
+
+  store.set(callEmbedAtom, asEmbed(embed));
+  store.set(callEmbedAtom, undefined);
+
+  assert.equal(embed.disposed, 1);
+  assert.equal(store.get(callEmbedAtom), undefined);
+});
+
+test('setting undefined when already undefined is a no-op', () => {
+  const store = createStore();
+  // No previous embed: the identity guard (undefined === undefined) returns early.
+  store.set(callEmbedAtom, undefined);
+  assert.equal(store.get(callEmbedAtom), undefined);
+});
diff --git a/src/app/state/closedNavCategories.test.ts b/src/app/state/closedNavCategories.test.ts
new file mode 100644
index 000000000..7ca2506f3
--- /dev/null
+++ b/src/app/state/closedNavCategories.test.ts
@@ -0,0 +1,104 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { createStore } from 'jotai';
+import { enableMapSet } from 'immer';
+import { makeClosedNavCategoriesAtom, makeNavCategoryId } from './closedNavCategories';
+
+// makeClosedNavCategoriesAtom(userId) builds a Set<string> atom whose reducer uses
+// immer produce (PUT add / DELETE delete) and persists to a per-user localStorage
+// key `closedNavCategories<userId>`. The reducers produce over a Set, so we enable
+// immer's Map/Set plugin (the app does this once at startup).
+// makeNavCategoryId joins args with '|'.
+enableMapSet();
+
+// In-memory localStorage so atomWithLocalStorage can read/write at construction
+// and on set. window is referenced for the onMount storage listener.
+type Store = Record<string, string>;
+const installLocalStorage = (): Store => {
+  const data: Store = {};
+  const ls = {
+    getItem: (k: string) => (k in data ? data[k] : null),
+    setItem: (k: string, v: string) => {
+      data[k] = String(v);
+    },
+    removeItem: (k: string) => {
+      delete data[k];
+    },
+  };
+  (globalThis as { localStorage?: unknown }).localStorage = ls;
+  (globalThis as { window?: unknown }).window = {
+    addEventListener: () => undefined,
+    removeEventListener: () => undefined,
+  };
+  return data;
+};
+
+test('makeNavCategoryId joins args with "|"', () => {
+  assert.equal(makeNavCategoryId('a', 'b', 'c'), 'a|b|c');
+  assert.equal(makeNavCategoryId('only'), 'only');
+  assert.equal(makeNavCategoryId(), '');
+});
+
+test('starts empty when nothing is stored', () => {
+  installLocalStorage();
+  const store = createStore();
+  const navAtom = makeClosedNavCategoriesAtom('@u:server');
+  assert.equal(store.get(navAtom).size, 0);
+});
+
+test('hydrates the Set from the per-user localStorage key', () => {
+  const data = installLocalStorage();
+  data['closedNavCategories@u:server'] = JSON.stringify(['x', 'y']);
+  const store = createStore();
+  const navAtom = makeClosedNavCategoriesAtom('@u:server');
+  assert.deepEqual(Array.from(store.get(navAtom)).sort(), ['x', 'y']);
+});
+
+test('PUT adds a category and DELETE removes it', () => {
+  installLocalStorage();
+  const store = createStore();
+  const navAtom = makeClosedNavCategoriesAtom('@u:server');
+
+  store.set(navAtom, { type: 'PUT', categoryId: 'cat1' });
+  assert.deepEqual(Array.from(store.get(navAtom)), ['cat1']);
+
+  store.set(navAtom, { type: 'DELETE', categoryId: 'cat1' });
+  assert.equal(store.get(navAtom).has('cat1'), false);
+});
+
+test('PUT of an existing category keeps the Set unchanged (idempotent)', () => {
+  installLocalStorage();
+  const store = createStore();
+  const navAtom = makeClosedNavCategoriesAtom('@u:server');
+  store.set(navAtom, { type: 'PUT', categoryId: 'cat1' });
+  store.set(navAtom, { type: 'PUT', categoryId: 'cat1' });
+  assert.equal(store.get(navAtom).size, 1);
+});
+
+test('DELETE of an absent category is a no-op', () => {
+  installLocalStorage();
+  const store = createStore();
+  const navAtom = makeClosedNavCategoriesAtom('@u:server');
+  store.set(navAtom, { type: 'DELETE', categoryId: 'missing' });
+  assert.equal(store.get(navAtom).size, 0);
+});
+
+test('writes persist to localStorage as an array', () => {
+  const data = installLocalStorage();
+  const store = createStore();
+  const navAtom = makeClosedNavCategoriesAtom('@u:server');
+  store.set(navAtom, { type: 'PUT', categoryId: 'cat1' });
+  assert.deepEqual(JSON.parse(data['closedNavCategories@u:server']), ['cat1']);
+});
+
+test('the storage key is namespaced per user', () => {
+  const data = installLocalStorage();
+  const store = createStore();
+  const aAtom = makeClosedNavCategoriesAtom('@a:server');
+  const bAtom = makeClosedNavCategoriesAtom('@b:server');
+
+  store.set(aAtom, { type: 'PUT', categoryId: 'only-a' });
+  assert.deepEqual(JSON.parse(data['closedNavCategories@a:server']), ['only-a']);
+  assert.equal(data['closedNavCategories@b:server'], undefined);
+  assert.equal(store.get(bAtom).size, 0);
+});
diff --git a/src/app/state/room-list/inviteList.test.ts b/src/app/state/room-list/inviteList.test.ts
new file mode 100644
index 000000000..9345d625b
--- /dev/null
+++ b/src/app/state/room-list/inviteList.test.ts
@@ -0,0 +1,52 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { createStore } from 'jotai';
+import { allInvitesAtom } from './inviteList';
+
+// allInvitesAtom shares the roomList reducer shape over an unexported string[]
+// baseRoomsAtom: INITIALIZE replace, PUT move-to-end dedupe, DELETE filter-out.
+// The React binding hook (useBindAllInvitesAtom) is not covered.
+
+const R1 = '!r1:server';
+const R2 = '!r2:server';
+const R3 = '!r3:server';
+
+test('starts empty', () => {
+  const store = createStore();
+  assert.deepEqual(store.get(allInvitesAtom), []);
+});
+
+test('INITIALIZE replaces the whole list', () => {
+  const store = createStore();
+  store.set(allInvitesAtom, { type: 'PUT', roomId: R1 });
+  store.set(allInvitesAtom, { type: 'INITIALIZE', rooms: [R2, R3] });
+  assert.deepEqual(store.get(allInvitesAtom), [R2, R3]);
+});
+
+test('PUT appends a new invite', () => {
+  const store = createStore();
+  store.set(allInvitesAtom, { type: 'PUT', roomId: R1 });
+  store.set(allInvitesAtom, { type: 'PUT', roomId: R2 });
+  assert.deepEqual(store.get(allInvitesAtom), [R1, R2]);
+});
+
+test('PUT of an existing invite moves it to the end (dedupe)', () => {
+  const store = createStore();
+  store.set(allInvitesAtom, { type: 'INITIALIZE', rooms: [R1, R2, R3] });
+  store.set(allInvitesAtom, { type: 'PUT', roomId: R1 });
+  assert.deepEqual(store.get(allInvitesAtom), [R2, R3, R1]);
+});
+
+test('DELETE removes an invite', () => {
+  const store = createStore();
+  store.set(allInvitesAtom, { type: 'INITIALIZE', rooms: [R1, R2, R3] });
+  store.set(allInvitesAtom, { type: 'DELETE', roomId: R2 });
+  assert.deepEqual(store.get(allInvitesAtom), [R1, R3]);
+});
+
+test('DELETE of an absent invite is a no-op', () => {
+  const store = createStore();
+  store.set(allInvitesAtom, { type: 'INITIALIZE', rooms: [R1] });
+  store.set(allInvitesAtom, { type: 'DELETE', roomId: R2 });
+  assert.deepEqual(store.get(allInvitesAtom), [R1]);
+});
diff --git a/src/app/state/room-list/roomList.test.ts b/src/app/state/room-list/roomList.test.ts
new file mode 100644
index 000000000..dd060e4cd
--- /dev/null
+++ b/src/app/state/room-list/roomList.test.ts
@@ -0,0 +1,55 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { createStore } from 'jotai';
+import { allRoomsAtom } from './roomList';
+
+// allRoomsAtom wraps an unexported baseRoomsAtom string[] reducer:
+//   INITIALIZE -> replace wholesale
+//   PUT        -> filter-out-then-push (move-to-end dedupe)
+//   DELETE     -> filter-out
+// We drive the reducer through a jotai store. The React binding hook
+// (useBindAllRoomsAtom) wires this to MatrixClient events and is not covered.
+
+const R1 = '!r1:server';
+const R2 = '!r2:server';
+const R3 = '!r3:server';
+
+test('starts empty', () => {
+  const store = createStore();
+  assert.deepEqual(store.get(allRoomsAtom), []);
+});
+
+test('INITIALIZE replaces the whole list', () => {
+  const store = createStore();
+  store.set(allRoomsAtom, { type: 'PUT', roomId: R1 });
+  store.set(allRoomsAtom, { type: 'INITIALIZE', rooms: [R2, R3] });
+  assert.deepEqual(store.get(allRoomsAtom), [R2, R3]);
+});
+
+test('PUT appends a new room', () => {
+  const store = createStore();
+  store.set(allRoomsAtom, { type: 'PUT', roomId: R1 });
+  store.set(allRoomsAtom, { type: 'PUT', roomId: R2 });
+  assert.deepEqual(store.get(allRoomsAtom), [R1, R2]);
+});
+
+test('PUT of an existing room moves it to the end (dedupe)', () => {
+  const store = createStore();
+  store.set(allRoomsAtom, { type: 'INITIALIZE', rooms: [R1, R2, R3] });
+  store.set(allRoomsAtom, { type: 'PUT', roomId: R1 });
+  assert.deepEqual(store.get(allRoomsAtom), [R2, R3, R1]);
+});
+
+test('DELETE removes a room', () => {
+  const store = createStore();
+  store.set(allRoomsAtom, { type: 'INITIALIZE', rooms: [R1, R2, R3] });
+  store.set(allRoomsAtom, { type: 'DELETE', roomId: R2 });
+  assert.deepEqual(store.get(allRoomsAtom), [R1, R3]);
+});
+
+test('DELETE of an absent room is a no-op', () => {
+  const store = createStore();
+  store.set(allRoomsAtom, { type: 'INITIALIZE', rooms: [R1] });
+  store.set(allRoomsAtom, { type: 'DELETE', roomId: R2 });
+  assert.deepEqual(store.get(allRoomsAtom), [R1]);
+});
diff --git a/src/app/state/room-list/utils.test.ts b/src/app/state/room-list/utils.test.ts
new file mode 100644
index 000000000..f55bcfcc2
--- /dev/null
+++ b/src/app/state/room-list/utils.test.ts
@@ -0,0 +1,35 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { compareRoomsEqual } from './utils';
+
+// compareRoomsEqual(a, b): length mismatch short-circuits to false, otherwise an
+// order-sensitive element-by-element equality. The React hook in the same file
+// (useBindRoomsWithMembershipsAtom) is not covered.
+
+test('two empty arrays are equal', () => {
+  assert.equal(compareRoomsEqual([], []), true);
+});
+
+test('identical arrays are equal', () => {
+  assert.equal(compareRoomsEqual(['a', 'b', 'c'], ['a', 'b', 'c']), true);
+});
+
+test('different lengths are not equal', () => {
+  assert.equal(compareRoomsEqual(['a', 'b'], ['a', 'b', 'c']), false);
+  assert.equal(compareRoomsEqual(['a'], []), false);
+});
+
+test('same elements in a different order are not equal (order-sensitive)', () => {
+  assert.equal(compareRoomsEqual(['a', 'b'], ['b', 'a']), false);
+});
+
+test('a single differing element makes them unequal', () => {
+  assert.equal(compareRoomsEqual(['a', 'b', 'c'], ['a', 'x', 'c']), false);
+});
+
+test('reference equality is not required, only value equality', () => {
+  const a = ['a', 'b'];
+  const b = ['a', 'b'];
+  assert.notEqual(a, b);
+  assert.equal(compareRoomsEqual(a, b), true);
+});
diff --git a/src/app/state/toast.test.ts b/src/app/state/toast.test.ts
new file mode 100644
index 000000000..fbceedffe
--- /dev/null
+++ b/src/app/state/toast.test.ts
@@ -0,0 +1,87 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { createStore } from 'jotai';
+import { toastQueueAtom, dismissToastAtom, ToastNotif } from './toast';
+
+// The queue lives in an unexported baseAtom; we drive the two write-only setters
+// (toastQueueAtom append + null no-op guard, dismissToastAtom remove-by-id)
+// through a jotai store and read back via toastQueueAtom's getter.
+
+const makeToast = (id: string): ToastNotif => ({
+  id,
+  displayName: `name-${id}`,
+  body: `body-${id}`,
+  roomName: `room-${id}`,
+  roomId: `!${id}:server`,
+});
+
+test('starts empty', () => {
+  const store = createStore();
+  assert.deepEqual(store.get(toastQueueAtom), []);
+});
+
+test('toastQueueAtom appends in order', () => {
+  const store = createStore();
+  const a = makeToast('a');
+  const b = makeToast('b');
+  store.set(toastQueueAtom, a);
+  store.set(toastQueueAtom, b);
+  assert.deepEqual(
+    store.get(toastQueueAtom).map((t) => t.id),
+    ['a', 'b'],
+  );
+  assert.equal(store.get(toastQueueAtom)[0], a);
+});
+
+test('toastQueueAtom ignores null (no-op guard)', () => {
+  const store = createStore();
+  store.set(toastQueueAtom, makeToast('a'));
+  store.set(toastQueueAtom, null);
+  assert.deepEqual(
+    store.get(toastQueueAtom).map((t) => t.id),
+    ['a'],
+  );
+});
+
+test('toastQueueAtom allows duplicate ids (no dedupe)', () => {
+  const store = createStore();
+  store.set(toastQueueAtom, makeToast('a'));
+  store.set(toastQueueAtom, makeToast('a'));
+  assert.equal(store.get(toastQueueAtom).length, 2);
+});
+
+test('dismissToastAtom removes the matching id only', () => {
+  const store = createStore();
+  store.set(toastQueueAtom, makeToast('a'));
+  store.set(toastQueueAtom, makeToast('b'));
+  store.set(toastQueueAtom, makeToast('c'));
+
+  store.set(dismissToastAtom, 'b');
+  assert.deepEqual(
+    store.get(toastQueueAtom).map((t) => t.id),
+    ['a', 'c'],
+  );
+});
+
+test('dismissToastAtom removes every entry sharing the id', () => {
+  const store = createStore();
+  store.set(toastQueueAtom, makeToast('a'));
+  store.set(toastQueueAtom, makeToast('a'));
+  store.set(toastQueueAtom, makeToast('b'));
+
+  store.set(dismissToastAtom, 'a');
+  assert.deepEqual(
+    store.get(toastQueueAtom).map((t) => t.id),
+    ['b'],
+  );
+});
+
+test('dismissToastAtom for an unknown id is a no-op', () => {
+  const store = createStore();
+  store.set(toastQueueAtom, makeToast('a'));
+  store.set(dismissToastAtom, 'missing');
+  assert.deepEqual(
+    store.get(toastQueueAtom).map((t) => t.id),
+    ['a'],
+  );
+});