Sorry Robert, the App Store approach adds absolutely no security to a product like Lazarus. The only way it could is if "they", were to go over the source code, line by line, looking for something that should not be there. Can you imagine how long that would take each time Lazarus has a release ? And their chance of finding something well hidden ?
Debian them selves do have some FPC/Lazarus people, I doubt the other distros do.
No, they rely on the reputation of the product, they see Lazarus is open source and that people are openly invited to examine and contribute to the code and reason that a conspiracy would be just too hard to hide. In the case of Ubuntu, they just take it from Debian.
So, getting Lazarus from your App Store is no safer, indeed, may be a little less safe because its been through several extra sets of hands, than direct from Lazarus's own distribution means.
https://wiki.freepascal.org/Installing_Lazarus_on_LinuxThat being said, I am surprised that the Ubuntu version of Lazarus is broken, they get it pretty much direct from Debian and while its most certainly not how I suggest you set it up, it does work. Hmm, unless you have the one intended for Bullseye, it had a self build problem that has been fixed in BackPorts.
You did not say what version of Ubuntu you are using and I cannot possibly read the error message you posted. Mind if I suggest that as a software developer your self, you should know better than that ?
Davo