Hei,
using the key "f" in the version 9.6.0.0020 running with macOS Monterey public beta sends the application to or from fullscreen. Even when using it in the notes-editor during typing... obviously this is not what you would expect, when writing down notes [;)]
I'm using a workaround, using system settings and overriding the "fullscreen" or "back to normal" shorcut from the window-menu.
Regards