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.
It’s a known and documented issue that Ubuntu does. They secretly install the Snap version, even if you tried to install the Deb package. This is an issue since years: https://askubuntu.com/questions/1345385/how-can-i-stop-apt-from-installing-snap-packages (posted 3 years and 7 months ago)