There is something that I don't understand: I've created a new project with a Safari Extension App in the macOS tab. I've allowed unsigned extension to be installed in Safari. So when I'm running the extension, I open the Safari Preferences and enable the extension. But then nothing... No button added in the bar (there is one by default in the target), no breakpoint triggered, and the extension seems to not have the authorisations to read, modify and send content from web pages. In a WWDC video about Safari App Extension it works directly. Does anyone has an idea? I'm using Xcode 11.2.1, Safari 13.0.3 and macOS 10.15.1.
Well I found from where the issue comes from. Each time you are running your (Safari app) extension you must select an app to run. By default I choose Safari (seems logic). But I didn't notice first that this action instantiate a new Safari. So each time you have to enable unsigned extensions, then enable your extension. Well now it's working fine. I hope this could help.