Overwrite macOS Sequoia FN-usage via BTT?

Hi Andreas, I am referring to this older post by myself. This was your answer:

" Andreas_HegenbergAdmin

Apr 2024

I think you should be able to record FN+F1 etc. in BTT. The system should not react to them anymore once configured in BTT."

Recap:

  1. What I want to do? Safari has an annoying FN + Arrowkeys behavior I want to overwrite.
  2. What I did? BTT assigning FN+Arrow-Keys but leave them blank, following "I think you should be able to record FN+F1 etc. in BTT. The system should not react to them anymore once configured in BTT."
  3. What is happening? This works with system stuff like display brightness up/ down. But not inside Safari.
  4. Question: How to force Safari to not scroll through the document if FN+Arrow is pressed. Instead, like with every App on my system, windows should be re-moved on the screen with FN+Arrowkeys.