Add Safari WebExtension build support and test

CLAUDE.md

@@ -9,18 +9,20 @@ npm install            # Install dependencies
 npm run build          # Build for Firefox (default)
 npm run build:firefox  # Build for Firefox
 npm run build:chrome   # Build for Chrome
+npm run build:safari   # Build for Safari
 npm run dev            # Run in Firefox Developer Edition
 npm run watch:chrome   # Watch mode for Chrome development
 npm run test           # Run unit tests (vitest)
 npm run lint           # ESLint check
 npm run build:types    # TypeScript type check
 npm run package        # Package for Firefox (web-ext-artifacts/)
 npm run package:chrome # Package for Chrome (ZIP)
+npm run package:safari # Build for Safari + run Apple's Safari Web Extension packager (outputs to web-ext-artifacts/safari/)
 ```
 
 ## Architecture
 
-**Cross-browser extension (Manifest V3)** for Firefox and Chrome that uses Fetch Proxy to trim ChatGPT conversations before React renders.
+**Cross-browser extension (Manifest V3)** for Firefox, Chrome, and Safari that uses Fetch Proxy to trim ChatGPT conversations before React renders.
 
 ### Core Components
 
@@ -60,17 +62,18 @@ LightSession Pro counts **messages** (role changes) instead of nodes:
 
 ```
 extension/
-├── manifest.json          # Symlink → manifest.firefox.json (or chrome copy)
+├── manifest.json          # Symlink → manifest.firefox.json (or chrome/safari copy)
 ├── manifest.firefox.json  # Firefox-specific manifest
 ├── manifest.chrome.json   # Chrome-specific manifest
+├── manifest.safari.json   # Safari-specific manifest (MV3, no declarativeContent)
 └── src/
     ├── page/              # Page script (Fetch Proxy, runs in page context)
     ├── content/           # Content scripts (settings, status bar)
     ├── background/        # Background service worker
     ├── popup/             # Popup HTML/CSS/TS
     └── shared/            # Types, constants, storage, logger
 tests/                     # Unit tests (vitest + happy-dom)
-build.cjs                  # esbuild build script (supports --target=firefox|chrome)
+build.cjs                  # esbuild build script (supports --target=firefox|chrome|safari)
 ```
 
 ## Conventions

README.md

@@ -65,6 +65,10 @@ Built after too many coding sessions where a single ChatGPT tab would start eati
 
 **[Install from Chrome Web Store](https://chromewebstore.google.com/detail/lightsession-pro/cenmillohidhjjjjiocmddkgmlonaigp)**
 
+### Safari
+
+Currently manual install only.
+
 ### After installation
 
 1. Open any ChatGPT conversation.
@@ -84,6 +88,9 @@ npm run build:firefox
 
 # Build for Chrome
 npm run build:chrome
+
+# Build for Safari
+npm run build:safari
 ```
 
 **Firefox:**
@@ -97,6 +104,14 @@ npm run build:chrome
 3. Click **Load unpacked**
 4. Select the `extension/` folder
 
+**Safari:**
+1. Run `npm run build:safari`
+2. Open **Safari > Settings > Developer**
+3. Click **Add Temporary Extension...**
+4. Select the `extension/` folder
+
+Temporary Safari extensions are for local testing/use. Safari may remove them after 24 hours or when Safari quits, so repeat the last steps after rebuilding or restarting Safari.
+
 ---
 
 ## 🚀 Usage
@@ -177,7 +192,7 @@ Trimming only affects what the browser renders. The conversation itself remains
 
 - Node.js >= 24.10.0 (see `.node-version`)
 - npm >= 10
-- Firefox >= 115 or Chrome >= 120
+- Firefox >= 115, Chrome >= 120, or Safari >= 15.4
 
 ### Scripts
 
@@ -188,6 +203,7 @@ npm install              # Install dependencies
 npm run build            # Build for Firefox (default)
 npm run build:firefox    # Build for Firefox
 npm run build:chrome     # Build for Chrome
+npm run build:safari     # Build for Safari
 
 # Development
 npm run dev              # Run in Firefox Developer Edition
@@ -201,6 +217,7 @@ npm run build:types      # Type check
 # Package
 npm run package          # Package for Firefox (web-ext-artifacts/)
 npm run package:chrome   # Package for Chrome (ZIP)
+npm run package:safari   # Package for Safari with Xcode tooling (optional)
 ```
 
 ### Project structure
@@ -217,6 +234,7 @@ extension/
 ├── icons/              # Extension icons
 ├── manifest.firefox.json  # Firefox manifest (MV3)
 ├── manifest.chrome.json   # Chrome manifest (MV3)
+├── manifest.safari.json   # Safari manifest (MV3)
 └── manifest.json          # Active manifest (symlink/copy from build)
 ```
 
@@ -231,7 +249,7 @@ extension/
 
 ## 🌐 Compatibility
 
-- **Browsers:** Firefox >= 115, Chrome >= 120 (Manifest V3)
+- **Browsers:** Firefox >= 115, Chrome >= 120, Safari >= 15.4 (Manifest V3)
 - **OS:** Windows, macOS, Linux
 - **ChatGPT:** Optimized for the current UI (2025–2026), resilient to small layout changes
 

build.cjs

@@ -7,6 +7,7 @@
  *   node build.cjs                     - Development build for Firefox (default)
  *   node build.cjs --target=firefox    - Build for Firefox
  *   node build.cjs --target=chrome     - Build for Chrome
+ *   node build.cjs --target=safari     - Build for Safari
  *   node build.cjs --watch             - Watch mode for development
  *   NODE_ENV=production node build.cjs - Production build (minified, no sourcemaps)
  */
@@ -18,10 +19,10 @@ const path = require('path');
 const isWatch = process.argv.includes('--watch');
 const isProduction = process.env.NODE_ENV === 'production';
 
-// Parse --target=firefox|chrome (default: firefox)
+// Parse --target=firefox|chrome|safari (default: firefox)
 const targetArg = process.argv.find((arg) => arg.startsWith('--target='));
 const target = targetArg ? targetArg.split('=')[1] : 'firefox';
-const validTargets = ['firefox', 'chrome'];
+const validTargets = ['firefox', 'chrome', 'safari'];
 if (!validTargets.includes(target)) {
   console.error(`❌ Invalid target: ${target}. Use: ${validTargets.join(', ')}`);
   process.exit(1);
@@ -39,8 +40,8 @@ function copyManifest() {
     fs.unlinkSync(manifestDest);
   }
 
-  if (target === 'chrome') {
-    // For Chrome, copy manifest.chrome.json
+  if (target === 'chrome' || target === 'safari') {
+    // For Chrome/Safari, copy the target-specific manifest
     fs.copyFileSync(manifestSrc, manifestDest);
     console.log(`✓ Copied manifest.${target}.json → manifest.json`);
   } else {

extension/manifest.safari.json

@@ -0,0 +1,53 @@
+{
+  "manifest_version": 3,
+  "name": "LightSession Pro for ChatGPT",
+  "version": "1.7.4",
+  "description": "Keep ChatGPT fast by keeping only the last N messages in the DOM. Local-only.",
+  "icons": {
+    "16": "icons/icon-16.png",
+    "32": "icons/icon-32.png",
+    "48": "icons/icon-48.png",
+    "128": "icons/icon-128.png"
+  },
+  "action": {
+    "default_title": "LightSession Pro",
+    "default_popup": "popup/popup.html"
+  },
+  "permissions": ["storage", "tabs"],
+  "host_permissions": [
+    "*://chat.openai.com/*",
+    "*://chatgpt.com/*"
+  ],
+  "content_scripts": [
+    {
+      "matches": [
+        "*://chat.openai.com/*",
+        "*://chatgpt.com/*"
+      ],
+      "js": ["dist/page-inject.js"],
+      "run_at": "document_start"
+    },
+    {
+      "matches": [
+        "*://chat.openai.com/*",
+        "*://chatgpt.com/*"
+      ],
+      "js": ["dist/content.js"],
+      "run_at": "document_idle"
+    }
+  ],
+  "background": {
+    "service_worker": "dist/background.js"
+  },
+  "web_accessible_resources": [
+    {
+      "resources": ["dist/page-script.js", ".dev"],
+      "matches": ["*://chat.openai.com/*", "*://chatgpt.com/*"]
+    }
+  ],
+  "browser_specific_settings": {
+    "safari": {
+      "strict_min_version": "15.4"
+    }
+  }
+}

extension/src/shared/browser-polyfill.ts

@@ -4,6 +4,7 @@
  * Cross-browser compatibility layer for WebExtension APIs.
  * - Firefox: uses global `browser` object (Promise-based)
  * - Chrome: uses global `chrome` object (callback-based, but MV3 supports Promises)
+ * - Safari: Web Extensions API (browser/chrome); MV3 from Safari 15.4+
  *
  * Modern Chrome (MV3) supports Promise-based APIs similar to Firefox,
  * so we can use `chrome` directly as a drop-in replacement for `browser`.

package-safari.cjs

@@ -0,0 +1,56 @@
+#!/usr/bin/env node
+/**
+ * Package the built extension as a Safari Web Extension Xcode project.
+ *
+ * Apple renamed safari-web-extension-converter to safari-web-extension-packager.
+ * Prefer the current tool name, but keep the old name as a fallback for older
+ * Xcode installs.
+ */
+
+const { spawnSync } = require('child_process');
+
+const TOOLS = ['safari-web-extension-packager', 'safari-web-extension-converter'];
+const args = [
+  'extension',
+  '--project-location',
+  'web-ext-artifacts/safari',
+  '--app-name',
+  'LightSession Pro',
+  '--bundle-identifier',
+  'com.lightsession.pro',
+  '--macos-only',
+  '--swift',
+  '--copy-resources',
+  '--no-open',
+  '--no-prompt',
+  '--force',
+];
+
+function findTool() {
+  for (const tool of TOOLS) {
+    const result = spawnSync('xcrun', ['--find', tool], { stdio: 'ignore' });
+    if (result.status === 0) {
+      return tool;
+    }
+  }
+
+  return undefined;
+}
+
+const tool = findTool();
+
+if (!tool) {
+  console.error(
+    'Safari packaging requires full Xcode with safari-web-extension-packager installed.'
+  );
+  process.exit(1);
+}
+
+const result = spawnSync('xcrun', [tool, ...args], { stdio: 'inherit' });
+
+if (result.error) {
+  console.error(result.error.message);
+  process.exit(1);
+}
+
+process.exit(result.status ?? 1);

package.json

@@ -10,10 +10,12 @@
     "build": "node build.cjs",
     "build:firefox": "node build.cjs --target=firefox",
     "build:chrome": "node build.cjs --target=chrome",
+    "build:safari": "node build.cjs --target=safari",
     "build:types": "tsc --noEmit",
     "build:prod": "rm -f extension/.dev && NODE_ENV=production node build.cjs",
     "build:prod:firefox": "rm -f extension/.dev && NODE_ENV=production node build.cjs --target=firefox",
     "build:prod:chrome": "rm -f extension/.dev && NODE_ENV=production node build.cjs --target=chrome",
+    "build:prod:safari": "rm -f extension/.dev && NODE_ENV=production node build.cjs --target=safari",
     "watch": "node build.cjs --watch",
     "watch:chrome": "node build.cjs --target=chrome --watch",
     "lint": "eslint extension/src",
@@ -27,6 +29,7 @@
     "dev:stable": "npm run build:firefox && web-ext run --source-dir=extension --firefox=firefox --start-url='https://chat.openai.com'",
     "package": "npm run build:prod:firefox && web-ext build --source-dir=extension --artifacts-dir=web-ext-artifacts",
     "package:chrome": "npm run build:prod:chrome && cd extension && zip -r ../web-ext-artifacts/lightsession-chrome.zip . -x '*.ts' -x 'src/*' -x 'manifest.*.json'",
+    "package:safari": "npm run build:prod:safari && node package-safari.cjs",
     "clean": "rm -rf extension/dist extension/popup/popup.js web-ext-artifacts"
   },
   "keywords": [