Labels in Eclipse "going out of bounds"/overlapping (Linux/KDE)

Question

I have a graphical problem in Eclipse that I can't find a solution to: Labels/Text in the Project Explorer and other views are drawn "out of bounds" and overlap other views, like editors.  Here's a screenshot:

If the labels have decorations (e.g., Git, like in the screenshot), they have an additional black background, making the problem worse.

I've tried forcing GTK2, switching to other themes (GTK & Eclipse) and using older Eclipse versions, but the problem persists. I also have the exact same problem on another machine. Both use Arch with a pretty default KDE installation.

You can see details about my Eclipse installation here: https://pastebin.com/23dfQ37U

If you need any further details, I'll gladly provide them.