This is a request for a feature, not really a bug report, and I hope I am
filing it in the correct place.

I wish to be able to assign a different Desktop Background for each
workspace, to go with the different Workspace Name I can assign to each
workspace.  For example, I could name the third workspace "Mountain" and
put a picture of a mountain as the Desktop Background.

Ideally, the button on the switcher would have a custom color choice for
each workspace.  For example, I could name a workspace "Forest", put a
picture of a forest as the Desktop Background, and choose green as the
custom color of the button.  For "Mountain" I might choose grey.  The
custom color choice might be a border around the edge of the button (part
of the button itself), and should be used for the tint that shows the
currently selected workspace.  For example, if I click on the "Forest"
workspace button, it should highlight in green.

For even more extra special bonus points, the dialog for specifying the
custom Desktop Background could guess at a compatible color.  For example,
averaging the colors of the "Forest" picture might come out green, and then
select the closest available shade of green for the custom color.

I do not request an actual mini representation of the Desktop Background
image on the button, because I suspect it would look very busy.  And it
would be covered over by window representations most of the time anyway.

Thank you for your work on GNOME.