Convert Web Extension To Safari App Extension
Answer : You should be able to reuse Content Scripts from your Web-Extensions (but you need to rewrite code to be able to send/receive messages with "background"). Background script will have to be re-written in Swift or Objective-C. You need to developp: a Mac Host Application (which will be a companion to the Extension) : Swift or Objective-C (this app must have minimum features to pass Apple review - check the Apple guidelines for Mac Apps) the extension : in Swift or Objective-C + HTML/JS (as for other browsers) The code in Swift (or Obj-C) for the extension is the equivalent of the background page you have in Web Extensions. It will control the toolbar button, life-cycle of the extension and can talk with injected scripts. You have an (small) example on Apple website : https://developer.apple.com/documentation/safariservices/safari_app_extensions?changes=_2&language=objc You should not use Extension Builder anymore (accessible from Developer menu in Safari) since ...