bug#50141: Current part of emacs red, other parts blue

[Lars Ingebrigtsen <larsi@gnus.org>]

Eli Zaretskii <eliz@gnu.org> writes:

> Emacs's way to mark the current window is by changing the way the mode
> line is displayed.

There's also `cursor-in-non-selected-windows', which is another
kinda-sorta subtle indicator.

However, Dan's request has come up a number of times (e.g., bug#12056,
which I'm merging this with), so I'm wondering whether we should add
something like this...  or at least add some infrastructure that would
allow it.

The obvious thing would be to run something from `select-window', but I
don't see any obvious hook that we could be using there.  Am I missing
something?  I was thinking about adding a minor mode for changing
background colours in windows...

On the other hand, if we want to add this, perhaps it'd make more sense
to just add a new variable to change the background colour of
non-selected backgrounds directly.

-- 
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   bloggy blog: http://lars.ingebrigtsen.no