Is there a way to enable proper mouse support in GNU screen so that I can switch the focus between split windows using my mouse?
In other words, I'm looking for a mouse-driven alternative to typing 'C-a Tab'.
Also check Debian Sid (unstable), since according to the first answer found for the said post, Debian Unstable has the latest version/release thingy of GNU Screen.
This, however, may mean that you'll have to build Screen from source, which in of itself shouldn't be too difficult, but if you've never done this kind of thing before it can be a bit intimidating.
GNU screen does not use the mouse in any way.