I'm looking to replace Caps Lock behaviour with the "Left Alt"/"Meta" modifier, in GNOME / X11.
There are a few options to replace Caps Lock with Super, Ctrl, etc. in GNOME Tweak Tool, which seems to use
dconf internally, but there is no option to make Caps Lock behave as Meta there. Looking at
less /usr/share/X11/xkb/rules/evdev confirms that this is not due to Gnome Tweak Tool, but an artifact of such a (named) rule just missing generally in X11.
Simply remapping via
xmodmap -e 'keycode 66 = Alt_L' seems to work at first and actually sends Alt_L as confirmed by
xev, and the Caps Lock LED doesn't change anymore, but no Alt/Meta behaviour happens when I press the key. For instance, CapsLock+B does not go a word back in the terminal as Alt+B does.
How do I do this?