Graphical bug on Xubuntu 22.04

Hello, I just installed Taskmanager 1.5.2 on my Xubuntu 22.04.3. Technically, it works great (and thank you so much for doing it!), but it has a weird visual bug on graphs, which it didn't have on my previous installation of Xubuntu. I'm not sure how to describe it, but here's a screenshot.

PS: If that's relevant, if have a Thinkpad X250 with the Linux 6.2.0-33-generic kernel. Sorry if I'm a bit unclear, this is one of my first bug reports...