Are you able to give better instructions regarding how to upgrade the wallet for Ubuntu?
"How to update the Bitcoin 2 Core Wallet?
Just download the newest .zip/tar.gz file and copy the executable files in the bin folder to replace the ones you had installed already."
When I try to start the new bitcoin2-qt I get the message: Could not display "bitcoin2-qt"
There is no application installed for "shared library" files.
Do you want to search for an application to open this file?
Turns out that a few configuration flags were not set for that version so I compiled a more widely compatible Linux 64-bit version and updated
https://github.com/BITC2/bitcoin2/releases/download/2.2/bitcoin2-2.2.0-x86_64-linux-gnu.tar.gz.
So you can now download it and try again. Meanwhile, we'll test this more than just the quick test I did so far.
Unfortunately it still doesn't work.
When I check properties for the 2.1.5 files the file types are "executable (application/x-executable)"
When I check properties for the 2.2.0 files the file types are "shared library (application/x-sharedlib)"
You're right, it is because of executable hardening and Bitcoin's executables appear the same way on some Linux desktop environments. It works though if you execute it from the command line with ./bitcoin2-qt