I should clarify a few things:
Thank you. I just made a (wrong) assumption based on the naming scheme you used (which is very un-linuxy and more windowsy
)
I am actually using Pop!_OS 22.04, and not, strictly speaking, Ubuntu.
That should not (have to) matter. I did not hear you mention running something esoteric.
It is still strange though. If it would really be a (generic) problem then I assume more people would have had complained about the issue (so there might be something off)
Thank you for mentioning that strace "killed" your GUI, I was not sure if it could be of help. Unfortunately that is all the approaches I can think of atm unless compiling with debug info (-glh) would be able to shed a light.
To be able to determine it is not related to FPCUpDeluxe (which I think it isn't) the only way to make sure is compile manually from source (as intended) but that does require more of your time to get yourself more acquainted with the build-system (see also
wiki, but I personally think the instructions there are rather confusing and at times even contradictory for someone new).