Yeah, I’m also pretty sure that this is a Flatpak issue — an update for one of the affected Flatpaks came out, and it’s issue with the cursor is now fixed. I suspect that when an update for the other applications rolls out, then they will also be fixed. I’m not entirely sure what went wrong in the Flatpaks with Plasma 6, though — it’s rather interesting. Maybe something got changed in one of the desktop portals?