refac: improve multi browser support

src/manifests/safari.ts

@@ -0,0 +1,16 @@
+import { createManifest } from '../../lib/createManifest'
+import baseManifest from './manifest.json'
+
+const updatedSafariManifest = {
+  ...baseManifest,
+  browser_specific_settings: {
+    safari: {
+      strict_min_version: '15.4',
+      strict_max_version: '*',
+    },
+    // ^^^ https://developer.apple.com/documentation/safariservices/safari_web_extensions/optimizing_your_web_extension_for_safari#3743239
+    //     https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/browser_specific_settings#safari_properties
+  },
+}
+
+export const safari = createManifest(updatedSafariManifest, 'safari')