Undo old side discolor fix
Undoing the one-line colormap bleeding fix in !427 (merged) so we can be careful right before release.
I'm 90% sure the code is okay without negative side effects, but it would be a nice change of pace for me not to approve a merge so hastily.
For Jimita's branch, this would mean merging the latest master into his branch, and making sure nothing is changed in conflict resolution.
Updated code in !429 (closed).