The browser is qtwebengine based and they backported it to a semi recent version of Chromium.

As I said, the port started years ago. They already skipped 18.04. Once 20.04 actually works, an upgrade to 22.04 should not be so difficult as much less changed under the hood between those versions. You can’t constantly try to hit a moving target and 20.04 is still supported a few more years.