Can't run CommandSet extension

This is split from https://github.com/qtile/qtile/issues/2730

Qtile version: 0.18.2.dev130+g3fe5e0d1 Commit where problem starts: https://github.com/qtile/qtile/commit/4c0988c2e155ff33b0179d22db653454635be814 Xephyr log cannot grab keyboard

Test case

    EzKey("M-C-q", lazy.run_extension(extension.CommandSet(
        commands={
            'a': 'xterm'
            },
        foreground='#FF0000', selected_background='#FF0000')),
        desc='test'),

[m-col]

Awesome, I think it should work from X’s point of view, it’s just a matter of us doing it correctly 😃

[elParaguayo]

Thanks for splitting this out. We probably need @m-col to take a look too as the issue arose in that keybinding/swallowing commit.