Shift+Fn captured when Fn is set as shortcut key

[pabloab]

When used Fn (F12, F10 or any F key) the related Shift+Fn key is captured by quake-mode but do nothing. For example, when used with Gnome Terminal, Shift+F10 is used to show the context menu near the pointer (usually like mouse right-clic). If F10 is used to pop-up Gnome Terminal then Shift+F10 event never reach the app.

This is particular inconvenient when using F12 and byobu, since Shift+F12 toggle on/off Byobu's keybindings.

Tried with several virtual terminals and Fn keys. Also on Pop!_OS 22.04 and Ubuntu 20.04. Could reproduce the issue on all the cases.