MACOS problem to have customized toolbar with F16 F17 ... touch

Hi

I am on realthunder branch.
I have an issue with PIE menu. 
I am on macos Catalina 10,15,7

I create a custom toolbar which I want to call by pressing a key. When I assign a letter, I can call the customized toolbar.
When I assign one of the F keys (F16,F17...) I have nothing. The customized toolbar does not appear.

The tab key can call pie menu.

Thanks for your help
