I cannot reproduce the issue as well with "Änderungsvorschläge" on.
Tested Vanadium DS Note and FairEmail.

Eagle_Owl Well, we have already established that this is a problem specific to certain apps. So it's not the case for every app. And for the apps where this is the case, disabling everything helps.

But I still don't understand why such popular apps have these issues. This should affect almost all Android users, since most of them use the standard Android keyboard, right?

One app where the error occurs is, for example, Perplexity.

      Pewdue most of them use the standard Android keyboard, right?

      Nope, barely anyone uses the AOSP keyboard. It's just FOSS OS's like Graphene that use it for lack of a better alternative. There isn't a single Android vendor out there who would ship the AOSP keyboard.

        Oh, okay... So the bug will be there forever. Then the only solution is still to change the keyboard or to not use Suggestions or the app where the error happens.