Improve Linux vault shortcut

The current keyboard shortcut for opening the vault on Linux is CtrlShiftU. This is a poor choice because Ubuntu, one of the most popular desktop distros, binds CtrlShiftU to Unicode input, forcing you to first focus a non-input element, then hit CtrlShiftU to open the vault. (Worse, it’s not possible to close the vault either without first focusing a non-input element…)

We need to choose a shortcut for this that does not conflict with popular configurations.

+1 just moving over from macOS to Ubuntu and very annoying that I can’t pop open my vault at login anymore.