If you’ve recently updated to KDE Plasma 5.5, you may have noticed that minimizing your applications no longer produces a noticeable effect in the task manager. (In actuality, the status effect of minimized versus non-minimized applications is limited to a thin, gray outline around the application title–hardly something that conveys application state well enough to process visually at first glance.)
The fault of this change lies with this bug report posted almost 3 years ago. After much discussion, it was decided that 1) the “disabled” state of minimized applications was a mistake, 2) the minimized state makes it too difficult for some people to locate the gray scale application icon, and 3) no one wanted to add a configuration option to enable or disable this feature, so the next best thing was to rip it out. Now, I’ll be honest: Maybe I just happen to have better-than-average pattern matching capabilities in my visual cortex (doubtful), but the gray scale icons for minimized applications really don’t bother me. What does bother me is this change: It takes me twice as long to find minimized applications on the task manager. To say nothing of the fact that two or three people complaining incessantly for 3 years can effect such a substantial change on the rest of us who actually liked the feature…
Humorously, I didn’t notice this change during the initial update. Since I spread my work out across multiple desktops, I don’t often minimize my applications. This explains, at least in part, why it took three days for me to discover this problem and make a post about it (and why I blamed it on plasma-shell’s propensity to crash all the time, although that seemed like a reasonable explanation in lieu of anything more substantive).
The good news is that I traced it down to this commit which turned off the minimized gray scale display. As expected, removing this patch returns the task manager’s display of minimized applications to its previous state. The bad news is that, yes, you do need to recompile plasma-desktop from source. If you happen to use Arch Linux, I’ve put together a PKGBUILD containing the fix based off the PKGBUILD in ABS (hence why I haven’t yet changed any of the credits–I should note that this is not an official package). I’ll keep this updated as best as I can until such time that upstream finally settles on a better idea than a 1 pixel gray outline for non-minimized applications.
The rest of you will have to apply the patch and build the sources yourself. Sorry about that.