New Installation on Ubuntu 18.04 - Screen seems to want but only 22 works with this OS

I’m trying to get a new installation working (my system failed after removing some supposedly unused packages, sigh).

I installed libdc1394-22 which is appropriate for my OS version (18.04), and I ran “sudo apt build-dep psychtoolbox-3” which installed a bunch of packages. However, when I run "Screen(‘?’) i get the following error:

Invalid MEX-file ‘/usr/local/MATLAB/toolbox/Psychtoolbox/PsychBasic/Screen.mexa64’: cannot open shared object file: No such file or directory

Which suggests to me that the mex file is looking for version 25 of libdc1394 (which is for OS 20.04) instead of version 22. But perhaps I’m wrong. Do I need to recompile Screen? Some advice would be very helpful.

I see that at this point Ubuntu 18.04 is no longer recommended, so I’m working on upgrading to 20.04. If it’s possible to stay with 18.04 it would be helpful to know how.

Psychtoolbox 3.0.18 no longer supports anything older than Ubuntu 20.04 LTS. You could DownloadPsychtoolbox() with the ‘flavor’ parameter set to ‘Psychtoolobx-3.0.17’ to get the old - and officially unsupported in case of trouble - release, which was the last one to run on Ubuntu 18.04. You’d miss out on the currently most recent 348 bug fixes or improvements though.

If you decide to upgrade the OS instead, then Ubuntu 22.04-LTS would probably be the thing to try, as it has some nice improvements wrt. PTB, a few of them contributed by myself, and so far seems to be well behaved, as far as day to day use on 1 out of 3 development and test machine with AMD Polaris gpu goes. I intend to switch to 22.04 on all my machines within the next few months.