This might be of interest to those that use KDE:
Proposed solution is very intersesting.
Open Dolphin, and click: Hamburger Menu → Configure → Configure Dolphin…
Then, Interface → Status & Location Bars → Status Bar → Click “Full width” radio button → Apply.
Presto, free space shows again. If there’s more to this issue than a default configuration change, your post doesn’t give enough information for people to parse. All I see is a closed bug that seems to be not a bug, but instead a layout change that, like most of KDE, can usually be reverted/customized.
Proposed solution is out and out asinine.