Replace manifest file with createManifest function.

source/manifest.json

@@ -1,37 +0,0 @@
-{
-  "manifest_version": 2,
-  "name": "Fangs",
-  "description": "Inject custom DuckDuckGo Bangs into your browsing experience.",
-  "version": "0.1.3",
-  "permissions": [
-    "storage",
-    "tabs",
-    "webNavigation"
-  ],
-  "content_security_policy": "script-src 'self'; object-src 'self'; style-src 'unsafe-inline'",
-  "web_accessible_resources": [
-    "assets/**"
-  ],
-  "icons": {
-    "128": "assets/fangs-128.png"
-  },
-  "browser_action": {
-    "default_icon": {
-      "128": "assets/fangs-128.png"
-    }
-  },
-  "options_ui": {
-    "page": "options/index.html",
-    "open_in_tab": true
-  },
-  "background": {
-    "scripts": [
-      "background-scripts/initialize.ts"
-    ]
-  },
-  "applications": {
-    "gecko": {
-      "id": "{cbb8b06b-9d6f-42f2-9d8d-7581f411653c}"
-    }
-  }
-}

source/manifest.ts

@@ -0,0 +1,49 @@
+/* eslint-disable @typescript-eslint/naming-convention */
+
+export default function createManifest(
+  target: string,
+): Record<string, unknown> {
+  const manifest: Record<string, unknown> = {
+    name: 'Fangs',
+    description:
+      'Inject custom DuckDuckGo Bangs into your browsing experience.',
+    version: '0.1.3',
+    permissions: ['storage', 'tabs', 'webNavigation'],
+    options_ui: {
+      page: 'options/index.html',
+      open_in_tab: true,
+    },
+  };
+
+  const icons = {
+    128: 'assets/fangs-128.png',
+  };
+
+  const browserAction = {
+    default_icon: icons,
+  };
+
+  const backgroundScript = 'background-scripts/initialize.ts';
+
+  if (target === 'chromium') {
+    manifest.manifest_version = 3;
+    manifest.action = browserAction;
+    manifest.background = {
+      service_worker: backgroundScript,
+      type: 'module',
+    };
+  } else {
+    manifest.manifest_version = 2;
+    manifest.browser_action = browserAction;
+    manifest.background = {
+      scripts: [backgroundScript],
+    };
+    manifest.applications = {
+      gecko: {
+        id: '{cbb8b06b-9d6f-42f2-9d8d-7581f411653c}',
+      },
+    };
+  }
+
+  return manifest;
+}

vite.config.ts

@@ -9,6 +9,8 @@ import {defineConfig} from 'vite';
 import preactPreset from '@preact/preset-vite';
 import webExtension from 'vite-plugin-web-extension';
 
+import createManifest from './source/manifest.js';
+
 const targetBrowser = process.env.VITE_BROWSER ?? 'firefox';
 process.env.VITE_BROWSER = targetBrowser;
 
@@ -47,7 +49,7 @@ export default defineConfig({
     webExtension({
       assets: 'assets',
       browser: targetBrowser,
-      manifest: path.join(sourceDir, 'manifest.json'),
+      manifest: () => createManifest(targetBrowser),
       webExtConfig,
     }),
   ],