I‘m German and use English Layout. From time to time I have to write on umlaut. And I always type alt u u for ü. I think alt is the compose key here. Alt u just

I‘m German and use English Layout. From time to time I have to write on umlaut. And I always type alt u u for ü. I think alt is the compose key here. Alt u just adds dots and the second u gets combined. This works the same with öä (alt u a, alt u o). It also works with ~ but I never went that far since my problem is solved. I try to configure the same on Linux/windows but couldn‘t get the same keys to work so far. macOS only has one alt key and linux doesn’t allow the left alt as compose key. At least not in arch.