The bracket keys on European keyboards map to a different symbol than the bracket keys on a US English keyboard.
Resolving keyboard mapping variations is usually a fairly easy matter of trial and error.
The square parantheses used for trim operations are directly to the right of the P key on a US/English keyboard. On a Norwegian keyboard, directly to the right of the P is the Å key. Does it perform the same function as the [ left parantheses?
Alternately, square parantheses on the Norwegian keyboard are generated with Alt Gr-8 and Alt Gr-9. Do they work?
[ ] works when writing... but not in after effect.... this time I used alt + 8 and it also work on the other ALT key..
So I dont know why it is not working to trim in After effects