fix(status-bar): don't overcount trimmed messages

extension/src/content/content.ts

@@ -22,6 +22,7 @@ import {
 } from './status-bar';
 import { isEmptyChatView } from './chat-view';
 import { installUserCollapse, type UserCollapseController } from './user-collapse';
+import { isLightSessionRejection } from './rejection-filter';
 
 
 // ============================================================================
@@ -412,6 +413,23 @@ window.addEventListener('error', (event) => {
 });
 
 window.addEventListener('unhandledrejection', (event) => {
-  logError('Unhandled promise rejection:', event.reason);
-  event.preventDefault();
+  let extensionUrlPrefix: string | undefined;
+  try {
+    extensionUrlPrefix = browser?.runtime?.getURL?.('');
+  } catch {
+    extensionUrlPrefix = undefined;
+  }
+
+  // Do not suppress site (ChatGPT) errors. Only suppress if it clearly originates from LightSession.
+  const strictIsOurs = isLightSessionRejection(event.reason, extensionUrlPrefix);
+  const looseIsOurs = isLightSessionRejection(event.reason);
+
+  if (strictIsOurs || looseIsOurs) {
+    logError('Unhandled promise rejection:', event.reason);
+
+    // Only suppress default reporting if we are confident this originates from our extension.
+    if (strictIsOurs) {
+      event.preventDefault();
+    }
+  }
 });

extension/src/content/rejection-filter.ts

@@ -0,0 +1,49 @@
+/**
+ * Helpers for filtering global error events so we don't suppress site errors.
+ *
+ * The content script can observe `window` errors/rejections originating from the page.
+ * Calling `preventDefault()` on these events suppresses the browser's default reporting,
+ * so we must only suppress errors that are clearly caused by LightSession itself.
+ */
+
+export function isLightSessionRejection(
+  reason: unknown,
+  extensionUrlPrefix?: string,
+): boolean {
+  const parts: string[] = [];
+
+  if (typeof reason === 'string') {
+    parts.push(reason);
+  } else if (reason instanceof Error) {
+    if (typeof reason.message === 'string') parts.push(reason.message);
+    if (typeof reason.stack === 'string') parts.push(reason.stack);
+    if (typeof reason.name === 'string') parts.push(reason.name);
+  } else if (typeof reason === 'object' && reason !== null) {
+    const r = reason as Record<string, unknown>;
+    if (typeof r.message === 'string') parts.push(r.message);
+    if (typeof r.stack === 'string') parts.push(r.stack);
+    if (typeof r.name === 'string') parts.push(r.name);
+    // Some browsers use different keys on Error-like objects.
+    if (typeof r.filename === 'string') parts.push(r.filename);
+    if (typeof r.fileName === 'string') parts.push(r.fileName);
+  }
+
+  if (parts.length === 0) return false;
+
+  const haystack = parts.join('\n');
+
+  // The most reliable signal: our own extension base URL.
+  // If we have it, prefer it exclusively to avoid suppressing unrelated site errors.
+  if (extensionUrlPrefix) {
+    return haystack.includes(extensionUrlPrefix);
+  }
+
+  // Fallback heuristics (only used if runtime URL isn't available).
+  // Our logger prefix sometimes appears in thrown messages.
+  if (haystack.includes('LS:')) return true;
+
+  // Useful in dev builds / source maps.
+  if (haystack.includes('light-session')) return true;
+
+  return false;
+}

extension/src/content/status-bar.ts

@@ -19,7 +19,6 @@ type StatusBarState = 'active' | 'waiting' | 'all-visible' | 'unrecognized';
 
 let currentStats: StatusBarStats | null = null;
 let isVisible = true;
-let accumulatedTrimmed = 0;
 
 // Throttle status bar updates to reduce DOM writes during active chat
 let lastUpdateTime = 0;
@@ -174,21 +173,9 @@ function renderWaitingStatusBar(bar: HTMLElement): void {
  * Update the status bar with new stats (throttled, with change detection)
  */
 export function updateStatusBar(stats: StatusBarStats): void {
-  // Reset accumulated count when entering a new/empty chat
-  if (stats.totalMessages === 0) {
-    accumulatedTrimmed = 0;
-  }
-
-  // Accumulate trimmed count
-  if (stats.trimmedMessages > 0) {
-    accumulatedTrimmed += stats.trimmedMessages;
-  }
-
-  // Use accumulated count for display
-  const displayStats: StatusBarStats = {
-    ...stats,
-    trimmedMessages: accumulatedTrimmed,
-  };
+  // Page-script reports an absolute "currently hidden" count (not a delta),
+  // so the status bar must not accumulate across repeated status events.
+  const displayStats: StatusBarStats = stats;
 
   // Change detection: skip if stats haven't changed
   if (statsEqual(displayStats, currentStats)) {
@@ -298,15 +285,13 @@ export function removeStatusBar(): void {
   }
   currentStats = null;
   isVisible = false;
-  accumulatedTrimmed = 0;
   lastUpdateTime = 0;
 }
 
 /**
- * Reset accumulated trimmed counter (call on chat navigation)
+ * Reset status bar state (call on chat navigation / empty chat)
  */
 export function resetAccumulatedTrimmed(): void {
-  accumulatedTrimmed = 0;
   currentStats = null;
   pendingStats = null;
   if (pendingUpdateTimer !== null) {

tests/unit/rejection-filter.test.ts

@@ -0,0 +1,35 @@
+import { describe, expect, it } from 'vitest';
+
+import { isLightSessionRejection } from '../../extension/src/content/rejection-filter';
+
+describe('isLightSessionRejection', () => {
+  it('returns false for empty/unknown reasons', () => {
+    expect(isLightSessionRejection(undefined)).toBe(false);
+    expect(isLightSessionRejection(null)).toBe(false);
+    expect(isLightSessionRejection(123)).toBe(false);
+    expect(isLightSessionRejection({})).toBe(false);
+  });
+
+  it('matches when reason string contains LS:', () => {
+    expect(isLightSessionRejection('LS: boom')).toBe(true);
+  });
+
+  it('does not match LS: in message when extension URL is provided but not present', () => {
+    const prefix = 'chrome-extension://abc123/';
+    expect(isLightSessionRejection('LS: boom', prefix)).toBe(false);
+  });
+
+  it('matches when Error.stack contains the extension base URL', () => {
+    const prefix = 'chrome-extension://abc123/';
+    const err = new Error('nope');
+    // Simulate a stack that points at our bundled content script URL.
+    err.stack = `Error: nope\n    at doThing (${prefix}dist/content.js:1:1)`;
+    expect(isLightSessionRejection(err, prefix)).toBe(true);
+  });
+
+  it('does not match non-LightSession errors by default', () => {
+    const err = new Error('Some site error');
+    err.stack = `Error: Some site error\n    at foo (https://chatgpt.com/app.js:1:1)`;
+    expect(isLightSessionRejection(err)).toBe(false);
+  });
+});

tests/unit/status-bar.test.ts

@@ -56,6 +56,34 @@ describe('status bar behavior', () => {
     expect(resetBar?.textContent).toBe(WAITING_TEXT);
   });
 
+  it('does not accumulate trimmed messages across repeated status events', () => {
+    vi.useFakeTimers();
+    showStatusBar();
+
+    updateStatusBar({
+      totalMessages: 8,
+      visibleMessages: 3,
+      trimmedMessages: 5,
+      keepLastN: 3,
+    });
+    vi.advanceTimersByTime(TIMING.STATUS_BAR_THROTTLE_MS);
+
+    const bar = document.getElementById('lightsession-status-bar');
+    expect(bar?.textContent).toBe('LightSession · last 3 · 5 trimmed');
+
+    // Repeated status event with the same absolute "currently trimmed" count
+    updateStatusBar({
+      totalMessages: 8,
+      visibleMessages: 3,
+      trimmedMessages: 5,
+      keepLastN: 3,
+    });
+    vi.advanceTimersByTime(TIMING.STATUS_BAR_THROTTLE_MS);
+
+    const bar2 = document.getElementById('lightsession-status-bar');
+    expect(bar2?.textContent).toBe('LightSession · last 3 · 5 trimmed');
+  });
+
   it('refreshes the status bar if the DOM node is removed', () => {
     vi.useFakeTimers();
     showStatusBar();