@bcooksley, sure, I've resorted to brute force because I needed working setup ASAP...
Anyway, apparently over time Plasma created multiple activities but didn't show any in activities switcher, DBus interface shown 3 but switching them that way didn't work (or maybe those were identical).
Maybe something got broken during update or maybe that's unrelated file corruption (EXT4), since just now I've again lost desktop setup (wallpaper settings and desktop applets, panels unaffected) after upgrading 4.10.1 to 4.10.2 (I've got exact same issue at least once, maybe around 4.8.x o 4.9.x), #318020.

now 2 situations:
how to recreate

open say 8 Konsole icons and 8 Firefox icons

do a yum update

(1) run cursor over icon in panel
(2) click on icon in panel

part of the problem is how dim the choices are

making the effect useless

@landonmkelsey: Please provide a screenshot of your panel as detailed in the prior post I made.
I am guessing the lack of contrast between the entries is a separate issue correct?

right! whole display of minimized icons is faint

things were great before this last change

now we have 2 ways of visualizing minimized icons

test? minimize 10 konsoles or terminals

The only thing you can do to alleviate the minimized windows contrast issue is change to another Plasma theme I'm afraid, as this is controlled entirely by the Plasma theme.

how does one do that

You can change the Plasma theme in System Settings > Workspace Appearance > Desktop Theme. A number of themes are shipped as part of KDE, and other themes (unofficial) can be downloaded via "Get New Themes".