Created attachment 117614 [details] screenshot See the screenshot taken on Arch Linux please. Operating System: Arch Linux KDE Plasma Version: 5.14.90 KDE Frameworks Version: 5.54.0 Qt Version: 5.12.0
Looks like the icon doesn't have the right stylesheet?
https://phabricator.kde.org/R242:eddc6dec69398da6d8f9a7c2f2676093c17846fb
The changelog of frameworks 5.60 release lists this bug as fixed but it persists after I update to such release on Arch Linux. The following related bugs also persist: bug 363436 bug 398754
Please clear your icon cache (rm ~/.cache/icon-cache.kcache) and log out and back in again. If that fixes it, then you're hitting a known bug: Bug 403229.
Cleaning the icon cache did not help. However I can confirm that this bug and the ones mentioned in comment 3 are fixed on Neon unstable edition.
Ah, then I think these bugs only become fully fixed with Plasma 5.17 then, because that's when the local icon that was masking the breeze icons version was removed from the disk quota applet itself.