The extra mouse buttons (specifically those on the side, not the left or right buttons even though those don't work either) cannot be set as keyboard shortcuts for any keys.
Steps to reproduce the bug
Opening the keyboard shortcuts menu
Selecting a shortcut to change with left click
Pressing the extra mouse button to set it to the shortcut (which does nothing)
Environment details
Does the same with the browser version and offline version.
(Note: With google, 2 of the extra mouse buttons are automatically set to have you go forward and backward in your browsing history but I assume those can be changed somewhere in my browser settings.)
The extra mouse buttons (specifically those on the side, not the left or right buttons even though those don't work either) cannot be set as keyboard shortcuts for any keys.
Steps to reproduce the bug
Environment details