diff --git a/package-lock.json b/package-lock.json
index a0f4c488f..b6f5e5577 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -24,7 +24,6 @@
         "@tanstack/react-query": "5.100.13",
         "@tanstack/react-query-devtools": "5.100.13",
         "@tanstack/react-virtual": "3.13.25",
-        "@types/dompurify": "3.2.0",
         "@workadventure/noise-suppression": "0.0.4",
         "await-to-js": "3.0.0",
         "badwords-list": "2.0.1-4",
@@ -36,7 +35,6 @@
         "dayjs": "1.11.20",
         "deepfilternet3-noise-filter": "1.2.1",
         "domhandler": "6.0.1",
-        "dompurify": "3.4.5",
         "emojibase": "17.0.0",
         "emojibase-data": "17.0.0",
         "file-saver": "2.0.5",
@@ -75,7 +73,8 @@
         "slate-history": "0.113.1",
         "slate-react": "0.124.2",
         "styled-components": "6.4.2",
-        "ua-parser-js": "2.0.10"
+        "ua-parser-js": "2.0.10",
+        "workbox-precaching": "7.4.1"
       },
       "devDependencies": {
         "@lotusguild/element-call-embedded": "0.20.1-lotus.1",
@@ -2697,9 +2696,9 @@
       "dev": true
     },
     "node_modules/@matrix-org/matrix-sdk-crypto-wasm": {
-      "version": "18.3.0",
-      "resolved": "https://registry.npmjs.org/@matrix-org/matrix-sdk-crypto-wasm/-/matrix-sdk-crypto-wasm-18.3.0.tgz",
-      "integrity": "sha512-9a4feyt8QLysARu7PHKaRWT+wcCd+IYH074LXp9QK5WqfN4zUXueRhiSSMNT18Bm+8q3sBR/4zxDxOSDR0M8Kg==",
+      "version": "18.3.1",
+      "resolved": "https://registry.npmjs.org/@matrix-org/matrix-sdk-crypto-wasm/-/matrix-sdk-crypto-wasm-18.3.1.tgz",
+      "integrity": "sha512-VRjWhE1UgHnPpJ3b9B5+8z71ZC/HICFngPPFIN6ktzmUBKI5RusPujzbAQUoB3CgZ0yU58L99AfSQS4YTztSWw==",
       "license": "Apache-2.0",
       "engines": {
         "node": ">= 18"
@@ -3920,16 +3919,6 @@
       "dev": true,
       "license": "MIT"
     },
-    "node_modules/@types/dompurify": {
-      "version": "3.2.0",
-      "resolved": "https://registry.npmjs.org/@types/dompurify/-/dompurify-3.2.0.tgz",
-      "integrity": "sha512-Fgg31wv9QbLDA0SpTOXO3MaxySc4DKGLi8sna4/Utjo4r3ZRPdCt4UQee8BWr+Q5z21yifghREPJGYaEOEIACg==",
-      "deprecated": "This is a stub types definition. dompurify provides its own type definitions, so you do not need this installed.",
-      "license": "MIT",
-      "dependencies": {
-        "dompurify": "*"
-      }
-    },
     "node_modules/@types/estree": {
       "version": "1.0.8",
       "resolved": "https://registry.npmjs.org/@types/estree/-/estree-1.0.8.tgz",
@@ -4051,7 +4040,7 @@
       "version": "2.0.7",
       "resolved": "https://registry.npmjs.org/@types/trusted-types/-/trusted-types-2.0.7.tgz",
       "integrity": "sha512-ScaPdn1dQczgbl0QFTeTOmVHFULt394XJgOQNoyVhZ6r2vLnMLJfBPd53SB52T/3G36VI1/g2MZaX0cwDuXsfw==",
-      "devOptional": true
+      "dev": true
     },
     "node_modules/@types/ua-parser-js": {
       "version": "0.7.39",
@@ -6196,15 +6185,6 @@
         "node": ">=20.19.0"
       }
     },
-    "node_modules/dompurify": {
-      "version": "3.4.5",
-      "resolved": "https://registry.npmjs.org/dompurify/-/dompurify-3.4.5.tgz",
-      "integrity": "sha512-OrwIBKsdNSVEeubdJ1HBv/wNENRM9ytAVCv7YXt//A3vPdVMNuACRqK9mXCGCBW2ln7BT/A4X0jXHo2Gu89miA==",
-      "license": "(MPL-2.0 OR Apache-2.0)",
-      "optionalDependencies": {
-        "@types/trusted-types": "^2.0.7"
-      }
-    },
     "node_modules/domutils": {
       "version": "3.2.2",
       "resolved": "https://registry.npmjs.org/domutils/-/domutils-3.2.2.tgz",
@@ -13228,7 +13208,6 @@
       "version": "7.4.1",
       "resolved": "https://registry.npmjs.org/workbox-core/-/workbox-core-7.4.1.tgz",
       "integrity": "sha512-DT+vu46eh/2vRsSHTY4Xmc32Z1rr9PRlQUXr1Dx30ZuXRWwOsvZgGgcwxcasubQLQmbTNYZjv44LkBAQ4tT5tQ==",
-      "dev": true,
       "license": "MIT"
     },
     "node_modules/workbox-expiration": {
@@ -13269,7 +13248,6 @@
       "version": "7.4.1",
       "resolved": "https://registry.npmjs.org/workbox-precaching/-/workbox-precaching-7.4.1.tgz",
       "integrity": "sha512-cdr/9qByww7yzEp7zg/qI4ukUrrNjQLgN+ONQRpjy/VqGQXwkgHwr00KksGJK8v0VifwDXBb8a4cWNZH71jn3Q==",
-      "dev": true,
       "license": "MIT",
       "dependencies": {
         "workbox-core": "7.4.1",
@@ -13306,7 +13284,6 @@
       "version": "7.4.1",
       "resolved": "https://registry.npmjs.org/workbox-routing/-/workbox-routing-7.4.1.tgz",
       "integrity": "sha512-yubJGErZOusuidAenaL5ypfhQOa7urxP/f8E0ws7FPb4039RiWXUWBAyUkmUoOL/BcQGen3h0J8872d51IYxtA==",
-      "dev": true,
       "license": "MIT",
       "dependencies": {
         "workbox-core": "7.4.1"
@@ -13316,7 +13293,6 @@
       "version": "7.4.1",
       "resolved": "https://registry.npmjs.org/workbox-strategies/-/workbox-strategies-7.4.1.tgz",
       "integrity": "sha512-GZxpaw9NbmOelj7667uZ2kpk5BFpOGbO4X0qjwh5ls8XQ8C+Lha5LQchTiUzsTFSS+NlUpftYAyOVXvQUrcqOQ==",
-      "dev": true,
       "license": "MIT",
       "dependencies": {
         "workbox-core": "7.4.1"
diff --git a/package.json b/package.json
index b94e088c7..a57dc3b46 100644
--- a/package.json
+++ b/package.json
@@ -49,7 +49,6 @@
     "@tanstack/react-query": "5.100.13",
     "@tanstack/react-query-devtools": "5.100.13",
     "@tanstack/react-virtual": "3.13.25",
-    "@types/dompurify": "3.2.0",
     "@workadventure/noise-suppression": "0.0.4",
     "await-to-js": "3.0.0",
     "badwords-list": "2.0.1-4",
@@ -61,7 +60,6 @@
     "dayjs": "1.11.20",
     "deepfilternet3-noise-filter": "1.2.1",
     "domhandler": "6.0.1",
-    "dompurify": "3.4.5",
     "emojibase": "17.0.0",
     "emojibase-data": "17.0.0",
     "file-saver": "2.0.5",
@@ -100,7 +98,8 @@
     "slate-history": "0.113.1",
     "slate-react": "0.124.2",
     "styled-components": "6.4.2",
-    "ua-parser-js": "2.0.10"
+    "ua-parser-js": "2.0.10",
+    "workbox-precaching": "7.4.1"
   },
   "devDependencies": {
     "@lotusguild/element-call-embedded": "0.20.1-lotus.1",
diff --git a/src/app/components/editor/autocomplete/EmoticonAutocomplete.tsx b/src/app/components/editor/autocomplete/EmoticonAutocomplete.tsx
index 9a59cf6ab..5c2809a6a 100644
--- a/src/app/components/editor/autocomplete/EmoticonAutocomplete.tsx
+++ b/src/app/components/editor/autocomplete/EmoticonAutocomplete.tsx
@@ -1,4 +1,4 @@
-import React, { KeyboardEvent as ReactKeyboardEvent, useEffect, useMemo } from 'react';
+import React, { KeyboardEvent as ReactKeyboardEvent, useEffect, useMemo, useState } from 'react';
 import { Editor } from 'slate';
 import { Box, MenuItem, Text, toRem } from 'folds';
 import { Room } from 'matrix-js-sdk';
@@ -11,7 +11,7 @@ import { onTabPress } from '../../../utils/keyboard';
 import { createEmoticonElement, moveCursor, replaceWithElement } from '../utils';
 import { useRecentEmoji } from '../../../hooks/useRecentEmoji';
 import { useRelevantImagePacks } from '../../../hooks/useImagePacks';
-import { IEmoji, emojis } from '../../../plugins/emoji';
+import { IEmoji, emojis, loadEmojiData } from '../../../plugins/emoji';
 import { useKeyDown } from '../../../hooks/useKeyDown';
 import { mxcUrlToHttp } from '../../../utils/matrix';
 import { useMediaAuthentication } from '../../../hooks/useMediaAuthentication';
@@ -47,13 +47,32 @@ export function EmoticonAutocomplete({
   const imagePacks = useRelevantImagePacks(ImageUsage.Emoticon, imagePackRooms);
   const recentEmoji = useRecentEmoji(mx, 20);
 
+  // Lazily load emojibase data (see plugins/emoji `loadEmojiData`). Until it
+  // resolves, `emojis` is empty and autocomplete matches only custom-emoji
+  // packs; the unicode emoji list fills in once loaded.
+  const [loadedEmojis, setLoadedEmojis] = useState<IEmoji[]>(() => emojis);
+  useEffect(() => {
+    let alive = true;
+    loadEmojiData()
+      // Fresh array reference: loadEmojiData populates the module-level array
+      // IN PLACE, so state set to the same ref would bail out of re-rendering
+      // and the search list would never gain the unicode emojis.
+      .then((loaded) => {
+        if (alive) setLoadedEmojis(loaded.emojis.slice());
+      })
+      .catch(() => undefined);
+    return () => {
+      alive = false;
+    };
+  }, []);
+
   const searchList = useMemo(() => {
     const list: Array<EmoticonSearchItem> = [];
     return list.concat(
       imagePacks.flatMap((pack) => pack.getImages(ImageUsage.Emoticon)),
-      emojis,
+      loadedEmojis,
     );
-  }, [imagePacks]);
+  }, [imagePacks, loadedEmojis]);
 
   const [result, search, resetSearch] = useAsyncSearch(
     searchList,
diff --git a/src/app/components/emoji-board/EmojiBoard.tsx b/src/app/components/emoji-board/EmojiBoard.tsx
index a1550d79e..2c2af3121 100644
--- a/src/app/components/emoji-board/EmojiBoard.tsx
+++ b/src/app/components/emoji-board/EmojiBoard.tsx
@@ -8,6 +8,7 @@ import React, {
   useEffect,
   useMemo,
   useRef,
+  useState,
 } from 'react';
 import { Box, config, Icons, Scroll } from 'folds';
 import FocusTrap from 'focus-trap-react';
@@ -15,7 +16,7 @@ import { isKeyHotkey } from 'is-hotkey';
 import { Room } from 'matrix-js-sdk';
 import { atom, PrimitiveAtom, useAtom, useSetAtom } from 'jotai';
 import { useVirtualizer } from '@tanstack/react-virtual';
-import { IEmoji, emojiGroups, emojis } from '../../plugins/emoji';
+import { EmojiData, IEmoji, emojiGroups, emojis, loadEmojiData } from '../../plugins/emoji';
 import { useEmojiGroupLabels } from './useEmojiGroupLabels';
 import { useEmojiGroupIcons } from './useEmojiGroupIcons';
 import { preventScrollWithArrowKey, stopPropagation } from '../../utils/keyboard';
@@ -56,6 +57,33 @@ import { VirtualTile } from '../virtualizer';
 const RECENT_GROUP_ID = 'recent_group';
 const SEARCH_GROUP_ID = 'search_group';
 
+/**
+ * Lazily pull in the emojibase data (see plugins/emoji `loadEmojiData`). The
+ * `emojis`/`emojiGroups` arrays are populated in place once the promise
+ * resolves; we wrap them in a fresh object on load so React re-renders and the
+ * board fills in. Before that, both are empty and the board shows only custom
+ * image packs / recents (which is fleeting — the load starts on mount).
+ */
+const useEmojiData = (): EmojiData => {
+  const [data, setData] = useState<EmojiData>(() => ({ emojis, emojiGroups }));
+  useEffect(() => {
+    let alive = true;
+    loadEmojiData()
+      // Fresh array references (not just a fresh wrapper): downstream memos
+      // depend on the arrays themselves, which are populated IN PLACE — same
+      // refs would skip recompute and leave emoji search empty until remount.
+      .then((loaded) => {
+        if (alive)
+          setData({ emojis: loaded.emojis.slice(), emojiGroups: loaded.emojiGroups.slice() });
+      })
+      .catch(() => undefined);
+    return () => {
+      alive = false;
+    };
+  }, []);
+  return data;
+};
+
 type EmojiGroupItem = {
   id: string;
   name: string;
@@ -75,6 +103,7 @@ const useGroups = (
 
   const recentEmojis = useRecentEmoji(mx, 21);
   const labels = useEmojiGroupLabels();
+  const { emojiGroups: loadedEmojiGroups } = useEmojiData();
 
   const emojiGroupItems = useMemo(() => {
     const g: EmojiGroupItem[] = [];
@@ -99,7 +128,7 @@ const useGroups = (
       });
     });
 
-    emojiGroups.forEach((group) => {
+    loadedEmojiGroups.forEach((group) => {
       g.push({
         id: group.id,
         name: labels[group.id],
@@ -108,7 +137,7 @@ const useGroups = (
     });
 
     return g;
-  }, [mx, recentEmojis, labels, imagePacks, tab]);
+  }, [mx, recentEmojis, labels, imagePacks, tab, loadedEmojiGroups]);
 
   const stickerGroupItems = useMemo(() => {
     const g: StickerGroupItem[] = [];
@@ -177,6 +206,7 @@ function EmojiSidebar({ activeGroupAtom, packs, onScrollToGroup }: EmojiSidebarP
   const usage = ImageUsage.Emoticon;
   const labels = useEmojiGroupLabels();
   const icons = useEmojiGroupIcons();
+  const { emojiGroups: loadedEmojiGroups } = useEmojiData();
 
   const packLabels = useMemo(() => {
     const map = new Map<string, string | undefined>();
@@ -234,7 +264,7 @@ function EmojiSidebar({ activeGroupAtom, packs, onScrollToGroup }: EmojiSidebarP
         }}
       >
         <SidebarDivider />
-        {emojiGroups.map((group) => (
+        {loadedEmojiGroups.map((group) => (
           <GroupIcon
             key={group.id}
             active={activeGroupId === group.id}
@@ -409,13 +439,14 @@ export function EmojiBoard({
   const [emojiGroupItems, stickerGroupItems] = useGroups(tab, imagePacks);
   const groups = emojiTab ? emojiGroupItems : stickerGroupItems;
   const renderItem = useItemRenderer(tab);
+  const { emojis: loadedEmojis } = useEmojiData();
 
   const searchList = useMemo(() => {
     let list: Array<PackImageReader | IEmoji> = [];
     list = list.concat(imagePacks.flatMap((pack) => pack.getImages(usage)));
-    if (emojiTab) list = list.concat(emojis);
+    if (emojiTab) list = list.concat(loadedEmojis);
     return list;
-  }, [emojiTab, usage, imagePacks]);
+  }, [emojiTab, usage, imagePacks, loadedEmojis]);
 
   const [result, search, resetSearch] = useAsyncSearch(
     searchList,
diff --git a/src/app/hooks/useRecentEmoji.ts b/src/app/hooks/useRecentEmoji.ts
index 926075f51..c09fabf34 100644
--- a/src/app/hooks/useRecentEmoji.ts
+++ b/src/app/hooks/useRecentEmoji.ts
@@ -2,11 +2,26 @@ import { useEffect, useState } from 'react';
 import { ClientEvent, MatrixClient, MatrixEvent } from 'matrix-js-sdk';
 import { getRecentEmojis } from '../plugins/recent-emoji';
 import { AccountDataEvent } from '../../types/matrix/accountData';
-import { IEmoji } from '../plugins/emoji';
+import { IEmoji, loadEmojiData } from '../plugins/emoji';
 
 export const useRecentEmoji = (mx: MatrixClient, limit?: number): IEmoji[] => {
   const [recentEmoji, setRecentEmoji] = useState(() => getRecentEmojis(mx, limit));
 
+  // Recent emojis are resolved against the (now lazily loaded) emojibase data
+  // via getRecentEmojis. Recompute once loadEmojiData has populated it so the
+  // recent list fills in on first open.
+  useEffect(() => {
+    let alive = true;
+    loadEmojiData()
+      .then(() => {
+        if (alive) setRecentEmoji(getRecentEmojis(mx, limit));
+      })
+      .catch(() => undefined);
+    return () => {
+      alive = false;
+    };
+  }, [mx, limit]);
+
   useEffect(() => {
     const handleAccountData = (event: MatrixEvent) => {
       if (event.getType() !== AccountDataEvent.ElementRecentEmoji) return;
diff --git a/src/app/plugins/emoji.ts b/src/app/plugins/emoji.ts
index 2462b7ffe..9a86b90dd 100644
--- a/src/app/plugins/emoji.ts
+++ b/src/app/plugins/emoji.ts
@@ -1,7 +1,4 @@
-import { CompactEmoji, fromUnicodeToHexcode } from 'emojibase';
-import emojisData from 'emojibase-data/en/compact.json';
-import joypixels from 'emojibase-data/en/shortcodes/joypixels.json';
-import emojibase from 'emojibase-data/en/shortcodes/emojibase.json';
+import type { CompactEmoji } from 'emojibase';
 
 export type IEmoji = CompactEmoji & {
   shortcode: string;
@@ -24,57 +21,76 @@ export type IEmojiGroup = {
   emojis: IEmoji[];
 };
 
-export const getShortcodesFor = (hexcode: string): string[] | string | undefined =>
-  joypixels[hexcode] || emojibase[hexcode];
+export type EmojiData = {
+  emojis: IEmoji[];
+  emojiGroups: IEmojiGroup[];
+};
+
+type ShortcodeMap = Record<string, string | string[]>;
+
+/**
+ * PERF (lazy emojibase split): the heavy `emojibase-data` JSON (compact emoji
+ * data + the joypixels/emojibase shortcode maps, ~965 KB combined) used to be
+ * imported statically at module top-level. Because reaction/message rendering
+ * (`Reaction`, `scaleSystemEmoji`) import this module eagerly, that dragged the
+ * whole `emojibase` chunk into the initial (eager) bundle graph.
+ *
+ * It is now loaded on demand via `loadEmojiData()` (a memoized dynamic import).
+ * Only lazy emoji surfaces (EmojiBoard, EmoticonAutocomplete, recent-emoji)
+ * trigger the load. Anything that renders eagerly (reaction/emoji tooltips and
+ * aria-labels via `getShortcodeFor`) gracefully degrades to `undefined` until
+ * the data has been loaded — the visible emoji glyph itself never depended on
+ * this data, so on-screen UX is unchanged; the shortcode label simply resolves
+ * once emoji data is loaded. `getHexcodeForEmoji` is inlined below so it stays
+ * synchronous WITHOUT pulling the `emojibase` runtime into the eager graph.
+ */
+
+// Inlined from emojibase's `fromUnicodeToHexcode` so this synchronous helper
+// does not import the `emojibase` package (and thus the emojibase chunk) into
+// the eager graph. Kept byte-for-byte behaviourally identical.
+const SEQUENCE_REMOVAL_PATTERN = /200D|FE0E|FE0F/g;
+
+export const getHexcodeForEmoji = (unicode: string, strip = true): string => {
+  const hexcode: string[] = [];
+  [...unicode].forEach((codepoint) => {
+    let hex = codepoint.codePointAt(0)?.toString(16).toUpperCase() ?? '';
+    while (hex.length < 4) {
+      hex = `0${hex}`;
+    }
+    if (!strip || !hex.match(SEQUENCE_REMOVAL_PATTERN)) {
+      hexcode.push(hex);
+    }
+  });
+  return hexcode.join('-');
+};
+
+// Populated by loadEmojiData(); `undefined` until the data has been loaded.
+let joypixelsShortcodes: ShortcodeMap | undefined;
+let emojibaseShortcodes: ShortcodeMap | undefined;
+
+export const getShortcodesFor = (hexcode: string): string[] | string | undefined => {
+  if (!joypixelsShortcodes || !emojibaseShortcodes) return undefined;
+  return joypixelsShortcodes[hexcode] || emojibaseShortcodes[hexcode];
+};
 
 export const getShortcodeFor = (hexcode: string): string | undefined => {
-  const shortcode = joypixels[hexcode] || emojibase[hexcode];
+  const shortcode = getShortcodesFor(hexcode);
   return Array.isArray(shortcode) ? shortcode[0] : shortcode;
 };
 
-export const getHexcodeForEmoji = fromUnicodeToHexcode;
-
+// Shared, stable array references. They start empty and are populated in place
+// the first time loadEmojiData() resolves (mirroring the previous eager module
+// side-effect). React consumers await loadEmojiData() and re-render to observe
+// the populated data; non-React consumers (recent-emoji) read them after load.
 export const emojiGroups: IEmojiGroup[] = [
-  {
-    id: EmojiGroupId.People,
-    order: 0,
-    emojis: [],
-  },
-  {
-    id: EmojiGroupId.Nature,
-    order: 1,
-    emojis: [],
-  },
-  {
-    id: EmojiGroupId.Food,
-    order: 2,
-    emojis: [],
-  },
-  {
-    id: EmojiGroupId.Activity,
-    order: 3,
-    emojis: [],
-  },
-  {
-    id: EmojiGroupId.Travel,
-    order: 4,
-    emojis: [],
-  },
-  {
-    id: EmojiGroupId.Object,
-    order: 5,
-    emojis: [],
-  },
-  {
-    id: EmojiGroupId.Symbol,
-    order: 6,
-    emojis: [],
-  },
-  {
-    id: EmojiGroupId.Flag,
-    order: 7,
-    emojis: [],
-  },
+  { id: EmojiGroupId.People, order: 0, emojis: [] },
+  { id: EmojiGroupId.Nature, order: 1, emojis: [] },
+  { id: EmojiGroupId.Food, order: 2, emojis: [] },
+  { id: EmojiGroupId.Activity, order: 3, emojis: [] },
+  { id: EmojiGroupId.Travel, order: 4, emojis: [] },
+  { id: EmojiGroupId.Object, order: 5, emojis: [] },
+  { id: EmojiGroupId.Symbol, order: 6, emojis: [] },
+  { id: EmojiGroupId.Flag, order: 7, emojis: [] },
 ];
 
 export const emojis: IEmoji[] = [];
@@ -95,20 +111,51 @@ function getGroupIndex(emoji: IEmoji): number | undefined {
   return undefined;
 }
 
-emojisData.forEach((emoji) => {
-  const myShortCodes = getShortcodesFor(emoji.hexcode);
-  if (!myShortCodes) return;
-  if (Array.isArray(myShortCodes) && myShortCodes.length === 0) return;
+let emojiDataPromise: Promise<EmojiData> | undefined;
 
-  const em: IEmoji = {
-    ...emoji,
-    shortcode: Array.isArray(myShortCodes) ? myShortCodes[0] : myShortCodes,
-    shortcodes: Array.isArray(myShortCodes) ? myShortCodes : emoji.shortcodes,
-  };
+/**
+ * Lazily load emojibase data (dynamic import → the `emojibase` chunk). Memoized:
+ * the JSON is fetched/parsed and `emojis`/`emojiGroups` are built exactly once.
+ */
+export const loadEmojiData = (): Promise<EmojiData> => {
+  if (!emojiDataPromise) {
+    emojiDataPromise = (async (): Promise<EmojiData> => {
+      const [emojisModule, joypixelsModule, emojibaseModule] = await Promise.all([
+        import('emojibase-data/en/compact.json'),
+        import('emojibase-data/en/shortcodes/joypixels.json'),
+        import('emojibase-data/en/shortcodes/emojibase.json'),
+      ]);
 
-  const groupIndex = getGroupIndex(em);
-  if (groupIndex !== undefined) {
-    addEmojiToGroup(groupIndex, em);
-    emojis.push(em);
+      joypixelsShortcodes = joypixelsModule.default as ShortcodeMap;
+      emojibaseShortcodes = emojibaseModule.default as ShortcodeMap;
+
+      const emojisData = emojisModule.default as unknown as CompactEmoji[];
+      emojisData.forEach((emoji) => {
+        const myShortCodes = getShortcodesFor(emoji.hexcode);
+        if (!myShortCodes) return;
+        if (Array.isArray(myShortCodes) && myShortCodes.length === 0) return;
+
+        const em: IEmoji = {
+          ...emoji,
+          shortcode: Array.isArray(myShortCodes) ? myShortCodes[0] : myShortCodes,
+          shortcodes: Array.isArray(myShortCodes) ? myShortCodes : emoji.shortcodes,
+        };
+
+        const groupIndex = getGroupIndex(em);
+        if (groupIndex !== undefined) {
+          addEmojiToGroup(groupIndex, em);
+          emojis.push(em);
+        }
+      });
+
+      return { emojis, emojiGroups };
+    })();
+    // Don't cache a rejection: a transient chunk-load failure (e.g. mid-deploy
+    // 404) would otherwise permanently disable emoji data until a full reload.
+    emojiDataPromise = emojiDataPromise.catch((err) => {
+      emojiDataPromise = undefined;
+      throw err;
+    });
   }
-});
+  return emojiDataPromise;
+};
diff --git a/src/app/plugins/react-custom-html-parser.tsx b/src/app/plugins/react-custom-html-parser.tsx
index 35bc4bff1..f21f095ec 100644
--- a/src/app/plugins/react-custom-html-parser.tsx
+++ b/src/app/plugins/react-custom-html-parser.tsx
@@ -577,12 +577,12 @@ export const getReactCustomHtmlParser = (
             return (
               <span className={css.EmoticonBase}>
                 <span className={css.Emoticon()}>
-                  <img {...props} className={css.EmoticonImg} src={htmlSrc} />
+                  <img {...props} className={css.EmoticonImg} src={htmlSrc} loading="lazy" />
                 </span>
               </span>
             );
           }
-          if (htmlSrc) return <img {...props} className={css.Img} src={htmlSrc} />;
+          if (htmlSrc) return <img {...props} className={css.Img} src={htmlSrc} loading="lazy" />;
         }
       }
 
diff --git a/src/app/plugins/react-prism/ReactPrism.tsx b/src/app/plugins/react-prism/ReactPrism.tsx
index ab2e9320e..47320a0fb 100644
--- a/src/app/plugins/react-prism/ReactPrism.tsx
+++ b/src/app/plugins/react-prism/ReactPrism.tsx
@@ -2,307 +2,33 @@ import React, { MutableRefObject, ReactNode, useEffect, useRef } from 'react';
 
 import Prism from 'prismjs';
 
-import 'prismjs/components/prism-abap.js';
-import 'prismjs/components/prism-abnf.js';
-import 'prismjs/components/prism-actionscript.js';
-import 'prismjs/components/prism-ada.js';
-import 'prismjs/components/prism-agda.js';
-import 'prismjs/components/prism-al.js';
-import 'prismjs/components/prism-antlr4.js';
-import 'prismjs/components/prism-apacheconf.js';
-import 'prismjs/components/prism-apex.js';
-import 'prismjs/components/prism-apl.js';
-import 'prismjs/components/prism-applescript.js';
-import 'prismjs/components/prism-aql.js';
-import 'prismjs/components/prism-arff.js';
-import 'prismjs/components/prism-armasm.js';
-import 'prismjs/components/prism-arturo.js';
-import 'prismjs/components/prism-asciidoc.js';
-import 'prismjs/components/prism-asm6502.js';
-import 'prismjs/components/prism-asmatmel.js';
-import 'prismjs/components/prism-aspnet.js';
-import 'prismjs/components/prism-autohotkey.js';
-import 'prismjs/components/prism-autoit.js';
-import 'prismjs/components/prism-avisynth.js';
-import 'prismjs/components/prism-avro-idl.js';
-import 'prismjs/components/prism-awk.js';
-import 'prismjs/components/prism-bash.js';
-import 'prismjs/components/prism-basic.js';
-import 'prismjs/components/prism-batch.js';
-import 'prismjs/components/prism-bbcode.js';
-import 'prismjs/components/prism-bbj.js';
-import 'prismjs/components/prism-bicep.js';
-import 'prismjs/components/prism-birb.js';
-import 'prismjs/components/prism-bnf.js';
-import 'prismjs/components/prism-bqn.js';
-import 'prismjs/components/prism-brainfuck.js';
-import 'prismjs/components/prism-brightscript.js';
-import 'prismjs/components/prism-bro.js';
-import 'prismjs/components/prism-bsl.js';
-import 'prismjs/components/prism-c.js';
-import 'prismjs/components/prism-cfscript.js';
-import 'prismjs/components/prism-cil.js';
-import 'prismjs/components/prism-cilkc.js';
-import 'prismjs/components/prism-cilkcpp.js';
+// PERF: Prism used to import every bundled language (~574 KB lazy chunk). We now
+// ship a curated subset covering the languages actually seen in chat. Imports
+// MUST stay in dependency order (Prism component files assume their base grammar
+// is already registered): base grammars (markup/css/clike/javascript) first,
+// then languages that extend them (e.g. c→cpp, javascript→typescript,
+// markup+javascript→jsx, jsx+typescript→tsx, markup→markdown).
+import 'prismjs/components/prism-markup.js'; // markup / html / xml / svg
+import 'prismjs/components/prism-css.js';
 import 'prismjs/components/prism-clike.js';
-import 'prismjs/components/prism-clojure.js';
-import 'prismjs/components/prism-cmake.js';
-import 'prismjs/components/prism-cobol.js';
-import 'prismjs/components/prism-coffeescript.js';
-import 'prismjs/components/prism-concurnas.js';
-import 'prismjs/components/prism-cooklang.js';
-import 'prismjs/components/prism-coq.js';
+import 'prismjs/components/prism-javascript.js'; // js
+import 'prismjs/components/prism-json.js';
+import 'prismjs/components/prism-yaml.js';
+import 'prismjs/components/prism-bash.js'; // bash / shell / sh
+import 'prismjs/components/prism-python.js';
+import 'prismjs/components/prism-rust.js';
+import 'prismjs/components/prism-go.js';
+import 'prismjs/components/prism-java.js';
+import 'prismjs/components/prism-c.js';
 import 'prismjs/components/prism-cpp.js';
 import 'prismjs/components/prism-csharp.js';
-import 'prismjs/components/prism-cshtml.js';
-import 'prismjs/components/prism-csp.js';
-import 'prismjs/components/prism-css-extras.js';
-import 'prismjs/components/prism-css.js';
-import 'prismjs/components/prism-csv.js';
-import 'prismjs/components/prism-cue.js';
-import 'prismjs/components/prism-cypher.js';
-import 'prismjs/components/prism-d.js';
-import 'prismjs/components/prism-dart.js';
-import 'prismjs/components/prism-dataweave.js';
-import 'prismjs/components/prism-dax.js';
-import 'prismjs/components/prism-dhall.js';
-import 'prismjs/components/prism-diff.js';
-import 'prismjs/components/prism-dns-zone-file.js';
-import 'prismjs/components/prism-docker.js';
-import 'prismjs/components/prism-dot.js';
-import 'prismjs/components/prism-ebnf.js';
-import 'prismjs/components/prism-editorconfig.js';
-import 'prismjs/components/prism-eiffel.js';
-import 'prismjs/components/prism-ejs.js';
-import 'prismjs/components/prism-elixir.js';
-import 'prismjs/components/prism-elm.js';
-import 'prismjs/components/prism-erb.js';
-import 'prismjs/components/prism-erlang.js';
-import 'prismjs/components/prism-etlua.js';
-import 'prismjs/components/prism-excel-formula.js';
-import 'prismjs/components/prism-factor.js';
-import 'prismjs/components/prism-false.js';
-import 'prismjs/components/prism-firestore-security-rules.js';
-import 'prismjs/components/prism-flow.js';
-import 'prismjs/components/prism-fortran.js';
-import 'prismjs/components/prism-fsharp.js';
-import 'prismjs/components/prism-ftl.js';
-import 'prismjs/components/prism-gap.js';
-import 'prismjs/components/prism-gcode.js';
-import 'prismjs/components/prism-gdscript.js';
-import 'prismjs/components/prism-gedcom.js';
-import 'prismjs/components/prism-gettext.js';
-import 'prismjs/components/prism-gherkin.js';
-import 'prismjs/components/prism-git.js';
-import 'prismjs/components/prism-glsl.js';
-import 'prismjs/components/prism-gml.js';
-import 'prismjs/components/prism-gn.js';
-import 'prismjs/components/prism-go-module.js';
-import 'prismjs/components/prism-go.js';
-import 'prismjs/components/prism-gradle.js';
-import 'prismjs/components/prism-graphql.js';
-import 'prismjs/components/prism-groovy.js';
-import 'prismjs/components/prism-haml.js';
-import 'prismjs/components/prism-handlebars.js';
-import 'prismjs/components/prism-haskell.js';
-import 'prismjs/components/prism-haxe.js';
-import 'prismjs/components/prism-hcl.js';
-import 'prismjs/components/prism-hlsl.js';
-import 'prismjs/components/prism-hoon.js';
-import 'prismjs/components/prism-hpkp.js';
-import 'prismjs/components/prism-hsts.js';
-import 'prismjs/components/prism-http.js';
-import 'prismjs/components/prism-ichigojam.js';
-import 'prismjs/components/prism-icon.js';
-import 'prismjs/components/prism-icu-message-format.js';
-import 'prismjs/components/prism-idris.js';
-import 'prismjs/components/prism-iecst.js';
-import 'prismjs/components/prism-ignore.js';
-import 'prismjs/components/prism-inform7.js';
-import 'prismjs/components/prism-ini.js';
-import 'prismjs/components/prism-io.js';
-import 'prismjs/components/prism-j.js';
-import 'prismjs/components/prism-java.js';
-import 'prismjs/components/prism-javadoclike.js';
-import 'prismjs/components/prism-javascript.js';
-import 'prismjs/components/prism-javastacktrace.js';
-import 'prismjs/components/prism-jexl.js';
-import 'prismjs/components/prism-jolie.js';
-import 'prismjs/components/prism-jq.js';
-import 'prismjs/components/prism-js-extras.js';
-import 'prismjs/components/prism-js-templates.js';
-import 'prismjs/components/prism-json.js';
-import 'prismjs/components/prism-json5.js';
-import 'prismjs/components/prism-jsonp.js';
-import 'prismjs/components/prism-jsstacktrace.js';
-import 'prismjs/components/prism-jsx.js';
-import 'prismjs/components/prism-julia.js';
-import 'prismjs/components/prism-keepalived.js';
-import 'prismjs/components/prism-keyman.js';
-import 'prismjs/components/prism-kotlin.js';
-import 'prismjs/components/prism-kumir.js';
-import 'prismjs/components/prism-kusto.js';
-import 'prismjs/components/prism-latex.js';
-import 'prismjs/components/prism-latte.js';
-import 'prismjs/components/prism-less.js';
-import 'prismjs/components/prism-lilypond.js';
-import 'prismjs/components/prism-linker-script.js';
-import 'prismjs/components/prism-liquid.js';
-import 'prismjs/components/prism-lisp.js';
-import 'prismjs/components/prism-livescript.js';
-import 'prismjs/components/prism-llvm.js';
-import 'prismjs/components/prism-log.js';
-import 'prismjs/components/prism-lolcode.js';
-import 'prismjs/components/prism-lua.js';
-import 'prismjs/components/prism-magma.js';
-import 'prismjs/components/prism-makefile.js';
-import 'prismjs/components/prism-markdown.js';
-import 'prismjs/components/prism-markup-templating.js';
-import 'prismjs/components/prism-markup.js';
-import 'prismjs/components/prism-mata.js';
-import 'prismjs/components/prism-matlab.js';
-import 'prismjs/components/prism-maxscript.js';
-import 'prismjs/components/prism-mel.js';
-import 'prismjs/components/prism-mermaid.js';
-import 'prismjs/components/prism-metafont.js';
-import 'prismjs/components/prism-mizar.js';
-import 'prismjs/components/prism-mongodb.js';
-import 'prismjs/components/prism-monkey.js';
-import 'prismjs/components/prism-moonscript.js';
-import 'prismjs/components/prism-n1ql.js';
-import 'prismjs/components/prism-n4js.js';
-import 'prismjs/components/prism-nand2tetris-hdl.js';
-import 'prismjs/components/prism-naniscript.js';
-import 'prismjs/components/prism-nasm.js';
-import 'prismjs/components/prism-neon.js';
-import 'prismjs/components/prism-nevod.js';
-import 'prismjs/components/prism-nginx.js';
-import 'prismjs/components/prism-nim.js';
-import 'prismjs/components/prism-nix.js';
-import 'prismjs/components/prism-nsis.js';
-import 'prismjs/components/prism-objectivec.js';
-import 'prismjs/components/prism-ocaml.js';
-import 'prismjs/components/prism-odin.js';
-import 'prismjs/components/prism-opencl.js';
-import 'prismjs/components/prism-openqasm.js';
-import 'prismjs/components/prism-oz.js';
-import 'prismjs/components/prism-parigp.js';
-import 'prismjs/components/prism-parser.js';
-import 'prismjs/components/prism-pascal.js';
-import 'prismjs/components/prism-pascaligo.js';
-import 'prismjs/components/prism-pcaxis.js';
-import 'prismjs/components/prism-peoplecode.js';
-import 'prismjs/components/prism-perl.js';
-import 'prismjs/components/prism-php-extras.js';
-import 'prismjs/components/prism-php.js';
-import 'prismjs/components/prism-phpdoc.js';
-import 'prismjs/components/prism-plant-uml.js';
-import 'prismjs/components/prism-powerquery.js';
-import 'prismjs/components/prism-powershell.js';
-import 'prismjs/components/prism-processing.js';
-import 'prismjs/components/prism-prolog.js';
-import 'prismjs/components/prism-promql.js';
-import 'prismjs/components/prism-properties.js';
-import 'prismjs/components/prism-protobuf.js';
-import 'prismjs/components/prism-psl.js';
-import 'prismjs/components/prism-pug.js';
-import 'prismjs/components/prism-puppet.js';
-import 'prismjs/components/prism-pure.js';
-import 'prismjs/components/prism-purebasic.js';
-import 'prismjs/components/prism-purescript.js';
-import 'prismjs/components/prism-python.js';
-import 'prismjs/components/prism-q.js';
-import 'prismjs/components/prism-qml.js';
-import 'prismjs/components/prism-qore.js';
-import 'prismjs/components/prism-qsharp.js';
-import 'prismjs/components/prism-r.js';
-import 'prismjs/components/prism-reason.js';
-import 'prismjs/components/prism-regex.js';
-import 'prismjs/components/prism-rego.js';
-import 'prismjs/components/prism-renpy.js';
-import 'prismjs/components/prism-rescript.js';
-import 'prismjs/components/prism-rest.js';
-import 'prismjs/components/prism-rip.js';
-import 'prismjs/components/prism-roboconf.js';
-import 'prismjs/components/prism-robotframework.js';
-import 'prismjs/components/prism-ruby.js';
-import 'prismjs/components/prism-rust.js';
-import 'prismjs/components/prism-sas.js';
-import 'prismjs/components/prism-sass.js';
-import 'prismjs/components/prism-scala.js';
-import 'prismjs/components/prism-scheme.js';
-import 'prismjs/components/prism-scss.js';
-import 'prismjs/components/prism-shell-session.js';
-import 'prismjs/components/prism-smali.js';
-import 'prismjs/components/prism-smalltalk.js';
-import 'prismjs/components/prism-smarty.js';
-import 'prismjs/components/prism-sml.js';
-import 'prismjs/components/prism-solidity.js';
-import 'prismjs/components/prism-solution-file.js';
-import 'prismjs/components/prism-soy.js';
-import 'prismjs/components/prism-splunk-spl.js';
-import 'prismjs/components/prism-sqf.js';
 import 'prismjs/components/prism-sql.js';
-import 'prismjs/components/prism-squirrel.js';
-import 'prismjs/components/prism-stan.js';
-import 'prismjs/components/prism-stata.js';
-import 'prismjs/components/prism-stylus.js';
-import 'prismjs/components/prism-supercollider.js';
-import 'prismjs/components/prism-swift.js';
-import 'prismjs/components/prism-systemd.js';
-import 'prismjs/components/prism-t4-templating.js';
-import 'prismjs/components/prism-t4-vb.js';
-import 'prismjs/components/prism-tap.js';
-import 'prismjs/components/prism-tcl.js';
-import 'prismjs/components/prism-textile.js';
-import 'prismjs/components/prism-toml.js';
-import 'prismjs/components/prism-tremor.js';
+import 'prismjs/components/prism-diff.js';
+import 'prismjs/components/prism-docker.js';
+import 'prismjs/components/prism-markdown.js';
+import 'prismjs/components/prism-typescript.js'; // ts
+import 'prismjs/components/prism-jsx.js';
 import 'prismjs/components/prism-tsx.js';
-import 'prismjs/components/prism-tt2.js';
-import 'prismjs/components/prism-turtle.js';
-import 'prismjs/components/prism-twig.js';
-import 'prismjs/components/prism-typescript.js';
-import 'prismjs/components/prism-typoscript.js';
-import 'prismjs/components/prism-unrealscript.js';
-import 'prismjs/components/prism-uorazor.js';
-import 'prismjs/components/prism-uri.js';
-import 'prismjs/components/prism-v.js';
-import 'prismjs/components/prism-vala.js';
-import 'prismjs/components/prism-vbnet.js';
-import 'prismjs/components/prism-velocity.js';
-import 'prismjs/components/prism-verilog.js';
-import 'prismjs/components/prism-vhdl.js';
-import 'prismjs/components/prism-vim.js';
-import 'prismjs/components/prism-visual-basic.js';
-import 'prismjs/components/prism-warpscript.js';
-import 'prismjs/components/prism-wasm.js';
-import 'prismjs/components/prism-web-idl.js';
-import 'prismjs/components/prism-wgsl.js';
-import 'prismjs/components/prism-wiki.js';
-import 'prismjs/components/prism-wolfram.js';
-import 'prismjs/components/prism-wren.js';
-import 'prismjs/components/prism-xeora.js';
-import 'prismjs/components/prism-xml-doc.js';
-import 'prismjs/components/prism-xojo.js';
-import 'prismjs/components/prism-xquery.js';
-import 'prismjs/components/prism-yaml.js';
-import 'prismjs/components/prism-yang.js';
-import 'prismjs/components/prism-zig.js';
-import 'prismjs/components/prism-arduino.js';
-
-// Broken:
-//
-// import 'prismjs/components/prism-bison.js';
-// import 'prismjs/components/prism-chaiscript.js';
-// import 'prismjs/components/prism-core.js';
-// import 'prismjs/components/prism-crystal.js';
-// import 'prismjs/components/prism-django.js';
-// import 'prismjs/components/prism-javadoc.js';
-// import 'prismjs/components/prism-jsdoc.js';
-// import 'prismjs/components/prism-plsql.js';
-// import 'prismjs/components/prism-racket.js';
-// import 'prismjs/components/prism-sparql.js';
-// import 'prismjs/components/prism-t4-cs.js';
 
 import './ReactPrism.css';
 // using classNames .prism-dark .prism-light from ReactPrism.css
diff --git a/src/app/plugins/recent-emoji.test.ts b/src/app/plugins/recent-emoji.test.ts
index c23f99a6b..93a543132 100644
--- a/src/app/plugins/recent-emoji.test.ts
+++ b/src/app/plugins/recent-emoji.test.ts
@@ -3,7 +3,7 @@ import assert from 'node:assert/strict';
 import { MatrixClient, MatrixEvent } from 'matrix-js-sdk';
 import { addRecentEmoji, getRecentEmojis, IRecentEmojiContent } from './recent-emoji';
 import { AccountDataEvent } from '../../types/matrix/accountData';
-import { emojis } from './emoji';
+import { emojis, loadEmojiData } from './emoji';
 
 // A Map-backed MatrixClient stub supporting get/setAccountData.
 const createMx = () => {
@@ -25,6 +25,9 @@ const createMx = () => {
 const getStored = (store: Map<string, unknown>): IRecentEmojiContent['recent_emoji'] =>
   (store.get(AccountDataEvent.ElementRecentEmoji) as IRecentEmojiContent | undefined)?.recent_emoji;
 
+// Emoji data is now loaded lazily; populate `emojis` before the round trips.
+await loadEmojiData();
+
 // Pick two real unicode emojis to drive add->get round trips.
 const u1 = emojis[0].unicode;
 const u2 = emojis[1].unicode;
diff --git a/src/sw.ts b/src/sw.ts
index b098fd915..2b713dda2 100644
--- a/src/sw.ts
+++ b/src/sw.ts
@@ -1,7 +1,39 @@
 /// <reference lib="WebWorker" />
 
+import { precacheAndRoute, type PrecacheEntry } from 'workbox-precaching';
+
 export type {};
-declare const self: ServiceWorkerGlobalScope;
+declare const self: ServiceWorkerGlobalScope & {
+  // Replaced at build time by vite-plugin-pwa (injectManifest) with the list of
+  // hashed build assets to precache. See vite.config.js VitePWA injectManifest.
+  __WB_MANIFEST: Array<string | PrecacheEntry>;
+};
+
+/**
+ * PRECACHE (workbox-precaching). `self.__WB_MANIFEST` is replaced at build time
+ * by vite-plugin-pwa with the list of hashed build assets
+ * (assets/**\/*.{js,css,wasm}; see vite.config.js injectManifest.globPatterns).
+ *
+ * DEPLOY-SAFETY INVARIANTS (do not break):
+ *  1. index.html / navigations are NEVER precached or precache-routed. The
+ *     manifest globs only `assets/**` (content-hashed), so index.html (served
+ *     from the app root) is absent from it and navigation requests fall through
+ *     to the network — a new deploy is picked up immediately, no stale SPA
+ *     shell. We deliberately do NOT register a navigation route /
+ *     createHandlerBoundToURL fallback.
+ *  2. precacheAndRoute only matches its own manifest URLs (same-origin hashed
+ *     assets). It never matches the media-auth paths handled by the fetch
+ *     listener below — those are cross-origin homeserver URLs absent from the
+ *     manifest — so the existing media fetch behaviour is fully preserved. It
+ *     is registered before that listener; for a media request the precache
+ *     route finds no match and does not call respondWith, so the media handler
+ *     still runs.
+ *  3. Assets are content-hashed, so a changed asset ships under a new filename;
+ *     PrecacheController drops entries no longer in the current manifest on
+ *     activate, so the precache self-updates each deploy without unbounded
+ *     growth.
+ */
+precacheAndRoute(self.__WB_MANIFEST);
 
 type SessionInfo = {
   accessToken: string;
diff --git a/vite.config.js b/vite.config.js
index ac4b42d51..0f75a35d0 100644
--- a/vite.config.js
+++ b/vite.config.js
@@ -261,7 +261,19 @@ export default defineConfig({
       injectRegister: false,
       manifest: false,
       injectManifest: {
-        injectionPoint: undefined,
+        // PRECACHE (P5): emit `self.__WB_MANIFEST` into src/sw.ts so it can
+        // precacheAndRoute the hashed build assets. index.html is deliberately
+        // EXCLUDED from the manifest (globs only `assets/**`) so navigations
+        // stay network-first and a new deploy is picked up immediately — see
+        // the deploy-safety invariants documented in src/sw.ts.
+        injectionPoint: 'self.__WB_MANIFEST',
+        globPatterns: ['assets/**/*.{js,css,wasm}'],
+        // Assets are content-hashed, so the filename is the cache key — don't
+        // append a revision cache-busting param.
+        dontCacheBustURLsMatching: /assets\//,
+        // Raised above the 2 MB default so the ~5.5 MB matrix-sdk crypto wasm
+        // (hash-busted and hot on every session) is precached deliberately.
+        maximumFileSizeToCacheInBytes: 6 * 1024 * 1024,
         // codeSplitting: false is not yet supported by vite-plugin-pwa 1.3.0;
         // the inlineDynamicImports deprecation warning from Vite is from pwa internal build
       },