I'm trying to figure out how to change the font used in non-editor tabs in Visual Studio Code; right now this is what I'm getting (zoom the picture to better see what I'm referring to):

As you can see, a Serif font is used on these non-editor tabs (extension info, Git Graph tab, etc.), making it quite unpleasant and really hard to read.

This happened all of a sudden, I'm quite sure that it is not the default and a nicer and more readable Sans font was used before (like on the left panel), until this problem occurred. I've tried to find if it is possible to change this from inside VSC, but I'm only able to change the fonts used in the editor tabs.

I don't know why and how this behavior has started, and I'm not really sure if this issue is caused by VSC itself, by an extension, by the OS, or something else.

If it matters, I'm working on Linux, on a fully updated openSUSE Tumbleweed with KDE, and like I said this problem started to manifest itself only recently, it was not how it worked by default.

Any clue on how to solve this?