It seems that libpulse-dev only needs to be installed on the build machine. That is quite logical, it is a dev package. It also looks that pulse audio is picked by default, at least on new? linux versions.
OK, then let's make sure that this info gets in all the linux.buildXXX/HowToBuild files.
I am unable to test on the PI. I can't convince it to work with a bluetooth speaker so I guess I need a USB speaker.
I also notice that on the newest version of Raspberry PI OS seems not to get all the way through the build though there are no obvious errors. it stops right after the ar of vm.a, and does not do the libtool parts. Both the older PI 3 and the new PI 4 have the same packages installed after the installation but maybe a different base set.
this kind of information is incredibly important for new users who grab squeak and want to get things done. We should make sure there is on squeak.org a "tips and tricks" page, or series of items on the download page that help new users solve these kinds of issues. The last thing we want is for a new user to find themselves blocked and have to go to the mailing list to get help. In that arc from being blocked to asking for help many people may simply give up and we will, I believe, lose users that way.
So Bruce, this inf should be in HowToBuild, but all, it should also be on squeak.org, and prominently.