After creating a fresh installation of Ubuntu 24.04, I installed DEB Firefox from APT by following Mozilla’s instructions from here. But I noticed that it was secretly replaced with Snap Firefox. I was able to verify this by checking the About Firefox page. This is the third time I noticed this.
Yes, that’s the exact issue. Ubuntu does that for years. You use apt to install deb, but Ubuntu installs silently the Snap version. The article I linked was talking about that almost 4 years ago and talks about how to stop that. It’s an old issue not many are aware off.