fix(extension): harden chat and target tab lifecycle

Author: Shik3i

docs/CHANGELOG.md

@@ -4,7 +4,7 @@ All notable changes to the KoalaSync browser extension and relay server.
 
 ---
 
-## Unreleased
+## [v3.0.2] — 2026-07-31
 
 ### Added
 - **Extension: Quick reactions** — Adds six encrypted one-click reactions with a local choice between chat-only display and bounded falling reactions over the video.
@@ -13,6 +13,11 @@ All notable changes to the KoalaSync browser extension and relay server.
 ### Changed
 - **Extension: Real dock behavior** — Anchors the collapsed Koala chat launcher to the selected side, reserves a page column in normal and fullscreen layouts, and clips viewport-bound page layers away from the open dock; detached mode remains freely movable.
 - **Extension: Koala chat launcher** — Replaces the generic speech-bubble emoji with the KoalaSync extension icon plus a chat marker.
+- **Extension: Reliable long chat sends** — Accepts up to 5000 Unicode code points, splits them into at most ten compatible 500-codepoint messages, waits for each relay echo before clearing text, and suppresses chat notifications while the selected video tab is focused.
+
+### Fixed
+- **Extension: Strict target-tab lifecycle** — Fully deactivates playback, audio, heartbeat, observer, seek-bridge, and chat code before changing targets, cleans up superseded injections, and limits website-bridge status delivery to the KoalaSync site instead of broadcasting to every open tab.
+- **Extension: Tab switching and page restore** — Keeps ordinary tab changes idle and injection-free, makes selecting the same target idempotent, blocks delayed callbacks after teardown, and restores the existing target cleanly after Firefox back/forward-cache suspension.
 
 ## [v3.0.1] — 2026-07-26
 

docs/CHAT.md

@@ -49,7 +49,9 @@ the stamped value as AAD.
 
 ## Client policy
 
-- Maximum plaintext length: 500 Unicode code points.
+- Maximum plaintext length per relay message: 500 Unicode code points.
+- The composer accepts up to 5000 Unicode code points and sends them sequentially
+  as at most ten independently encrypted `chat-v1` messages.
 - Decrypted text is untrusted. Escape HTML before applying the supported limited
   Markdown formatting.
 - Quick reactions use the same encrypted message path as text. They remain readable
@@ -84,6 +86,10 @@ the stamped value as AAD.
 - Chat display is a local option and defaults to off. Enabling or disabling it never
   deletes the room chat secret, so it can be enabled later without creating a room.
 - Without the relay `chat` capability, no chat control is shown.
+- System notifications are suppressed while the selected video tab and its browser
+  window are focused.
+- A send succeeds only after the relay echoes the authenticated ciphertext back to
+  the sender. Unconfirmed and remaining split messages stay in the composer.
 
 ## Mixed-version rollout
 

extension/background.js

@@ -29,5 +29,41 @@
         return tokens;
     }
 
-    root.KoalaSyncChatFormat = Object.freeze({ escapeChatHtml, formatChatText, tokenizeChatText });
+    function splitChatText(value, maxCodePoints = 500, maxChunks = 10) {
+        if (!Number.isInteger(maxCodePoints) || maxCodePoints < 1 || !Number.isInteger(maxChunks) || maxChunks < 1) {
+            throw new TypeError('Chat chunk limits must be positive integers');
+        }
+        let remaining = [...String(value ?? '').trim()];
+        if (remaining.length === 0) return [];
+        if (remaining.length > maxCodePoints * maxChunks) {
+            throw new RangeError('Chat composer text exceeds the chunk limit');
+        }
+
+        const chunks = [];
+        while (remaining.length > 0) {
+            if (remaining.length <= maxCodePoints) {
+                chunks.push(remaining.join('').trim());
+                break;
+            }
+
+            const remainingSlots = maxChunks - chunks.length;
+            const minimumSplit = Math.max(1, remaining.length - (remainingSlots - 1) * maxCodePoints);
+            let splitAt = maxCodePoints;
+            for (let index = maxCodePoints - 1; index >= minimumSplit; index--) {
+                if (/\s/u.test(remaining[index])) {
+                    splitAt = index;
+                    break;
+                }
+            }
+
+            const chunk = remaining.slice(0, splitAt).join('').trim();
+            remaining = remaining.slice(splitAt);
+            while (remaining.length > 0 && /\s/u.test(remaining[0])) remaining.shift();
+            if (chunk) chunks.push(chunk);
+        }
+
+        return chunks;
+    }
+
+    root.KoalaSyncChatFormat = Object.freeze({ escapeChatHtml, formatChatText, tokenizeChatText, splitChatText });
 })(globalThis);

extension/chat-format.js

@@ -19,4 +19,25 @@ describe('chat formatting', () => {
             { type: 'em', text: 'italic' }
         ]);
     });
+
+    it('splits up to 5000 Unicode code points into at most ten ordered chat-v1 messages', () => {
+        const split = globalThis.KoalaSyncChatFormat.splitChatText;
+        expect(split('hello world', 500, 10)).toEqual(['hello world']);
+
+        const emojiChunks = split('😀'.repeat(1001), 500, 10);
+        expect(emojiChunks.map(chunk => [...chunk].length)).toEqual([500, 500, 1]);
+
+        const maximumChunks = split('x'.repeat(5000), 500, 10);
+        expect(maximumChunks).toHaveLength(10);
+        expect(maximumChunks.every(chunk => [...chunk].length === 500)).toBe(true);
+        expect(maximumChunks.join('')).toBe('x'.repeat(5000));
+
+        expect(() => split('x'.repeat(5001), 500, 10)).toThrow(RangeError);
+    });
+
+    it('prefers whitespace boundaries without creating more chunks than the limit allows', () => {
+        const split = globalThis.KoalaSyncChatFormat.splitChatText;
+        const chunks = split(`${'a'.repeat(420)} ${'b'.repeat(179)}`, 500, 10);
+        expect(chunks).toEqual(['a'.repeat(420), 'b'.repeat(179)]);
+    });
 });

extension/chat-format.test.mjs

@@ -1,5 +1,6 @@
 import fs from 'node:fs';
 import path from 'node:path';
+import vm from 'node:vm';
 import { fileURLToPath } from 'node:url';
 import { describe, expect, it } from 'vitest';
 
@@ -34,6 +35,15 @@ const chatKeys = [
 ];
 
 describe('chat overlay contract', () => {
+    it('skips SVG and other non-HTML documents before creating the overlay host', () => {
+        const documentGuard = "document.documentElement?.namespaceURI !== 'http://www.w3.org/1999/xhtml'";
+        expect(overlaySource).toContain(documentGuard);
+        expect(overlaySource.indexOf(documentGuard)).toBeLessThan(overlaySource.indexOf("document.createElement('div')"));
+        expect(() => vm.runInNewContext(overlaySource, {
+            document: { documentElement: { namespaceURI: 'http://www.w3.org/2000/svg' } }
+        })).not.toThrow();
+    });
+
     it('isolates the overlay and never renders markup as HTML', () => {
         expect(overlaySource).toContain("attachShadow({ mode: 'open' })");
         expect(overlaySource).not.toMatch(/\.innerHTML\s*=|insertAdjacentHTML|\.outerHTML\s*=/);
@@ -85,6 +95,7 @@ describe('chat overlay contract', () => {
         expect(overlaySource).toContain('margin-right: var(${PAGE_DOCK_WIDTH}) !important');
         expect(overlaySource).toContain('html[${PAGE_DOCK_ATTRIBUTE}] > body');
         expect(overlaySource).toContain('clip-path: inset(0) !important');
+        expect(overlaySource).toContain('contain: layout paint !important');
         expect(overlaySource).toContain('> :not(#koalasync-chat-overlay-host)');
         expect(overlaySource).toContain('const target = document.fullscreenElement || document.documentElement');
         expect(overlaySource).toContain('pageDockTarget = target');
@@ -100,7 +111,9 @@ describe('chat overlay contract', () => {
         expect(overlaySource).toContain("unreadBadge.classList.toggle('visible', unreadCount > 0)");
         expect(backgroundSource).toMatch(/received\.senderId !== peerId[\s\S]*showChatNotification\([\s\S]*senderPeer\.username[\s\S]*received\.senderId/);
         expect(backgroundSource).toContain("chrome.notifications.create(`chat_${Date.now()}`");
-        expect(backgroundSource).toContain("if (settings.chatNotifications === false) return");
+        expect(backgroundSource).toContain('getTabForNotification(targetTabId)');
+        expect(backgroundSource).toContain('getWindowForNotification(tab.windowId)');
+        expect(backgroundSource).toContain('shouldShowChatNotification({ enabled, targetTabId, tab, windowInfo })');
     });
 
     it('renders timestamped room activity and keeps activity notifications opt-in', () => {
@@ -125,12 +138,24 @@ describe('chat overlay contract', () => {
         expect(overlaySource).toContain('launcherIcon.src = LAUNCHER_ICON_DATA_URL');
         expect(manifestSource).not.toContain('web_accessible_resources');
         expect(overlaySource).toContain("const QUICK_REACTIONS = Object.freeze(['❤️', '😂', '😮', '😢', '👏', '🔥'])");
-        expect(overlaySource).toContain("messageRuntime({ type: 'CHAT_SEND', text })");
+        expect(overlaySource).toContain("messageRuntime({ type: 'CHAT_SEND', text: chunk })");
         expect(overlaySource).toContain("chatReactionDisplay !== 'video'");
         expect(overlaySource).toContain('MAX_REACTION_PARTICLES - reactionLayer.childElementCount');
         expect(overlaySource).toContain('reducedMotion.matches');
     });
 
+    it('splits a 5000-codepoint composer value into at most ten acknowledged chat-v1 messages', () => {
+        expect(overlaySource).toContain('const MAX_MESSAGE_CODE_POINTS = 500');
+        expect(overlaySource).toContain('const MAX_CHAT_CHUNKS = 10');
+        expect(overlaySource).toContain('MAX_MESSAGE_CODE_POINTS * MAX_CHAT_CHUNKS');
+        expect(overlaySource).toContain('KoalaSyncChatFormat?.splitChatText(');
+        expect(overlaySource).toMatch(/for \(const chunk of chunks\)[\s\S]*messageRuntime\(\{ type: 'CHAT_SEND', text: chunk \}\)/);
+        expect(overlaySource).toContain("textarea.value = chunks.slice(completedChunks).join('\\n')");
+        expect(backgroundSource).toContain('const echoPromise = chatEchoTracker.waitFor(ciphertext)');
+        expect(backgroundSource).toContain('chatEchoTracker.acknowledge(received.ciphertext)');
+        expect(backgroundSource).toContain("status: acknowledged ? 'ok' : 'unconfirmed'");
+    });
+
     it('excludes test-only modules from production extension artifacts', () => {
         expect(buildSource).toContain("/\\.test\\.[cm]?js$/u.test(item)");
     });
@@ -143,6 +168,9 @@ describe('chat overlay contract', () => {
         expect(overlaySource).toContain('setTimeout(() => finish(null), timeoutMs)');
         expect(backgroundSource).toContain('chatReceiveQueue = chatReceiveQueue.catch(() => {}).then');
         expect(backgroundSource).toContain("status: 'rate_limited'");
+        expect(overlaySource).toContain('function setLocalStorage(values)');
+        expect(overlaySource).toMatch(/chrome\.storage\.local\.get\([\s\S]*data => \{\s*if \(destroyed\) return;/);
+        expect(overlaySource).toContain("if (destroyed || area !== 'local') return");
     });
 
     it('keeps chat hidden by default without discarding the room chat key', () => {