I am pretty sure the four errors have nothing to to with your printing problem. They seem to be an issue inside the printer dialog, but nothing which prevents you from printing. Are you sure myPrintView is valid?

The strange certificate came from a settings error I made in the configuration file of the framework I use (Quasar). I got the https configuration for the development server wrong and Quasar issued an ad-hoc certificate instead of using the certificate I provided. So my question boils down to why Safari won't let me accept the certificate on one of the Macs. But maybe an even better solution for that last problem: I added the mkcert root CA and the certificate I signed with this CA to my keychain, now Safari accepts https connections to localhost.

Same here. I run Xcode 15.2 on Sonoma 14.2, iMac Retina 5K, 27", 2019, 3,6 GHz 8-Core Intel Core i9. I have a fairly large and old project, but debugging iOS stopped working after update to Xcode 15. I did not see NSLog messages any more (console is visible, of course) and breakpoints got ignored if I did not start the iOS app manually instead of automatically. To see if project settings could be the culprit I made a new project from Xcode app template. Debugging worked flawlessly. Then I tried my old project again without changing anything and now everything works.

Same here. I run Xcode 15.2 on Sonoma 14.2, iMac Retina 5K, 27", 2019, 3,6 GHz 8-Core Intel Core i9. I have a fairly large and old project which I really depend on, but debugging iOS stopped working reliably. I do not see NSLog messages any more (console is visible, of course) and breakpoints get ignored if I do not start the iOS app manually instead of from the scheme. But on the same machine I can debug a new project right from a template fine. I did not find out which project settings could be wrong yet. I think this started when I installed Xcode 15, coming from Xcode 14. Did you try to debug a blank new project already?

I had the same question which was obviously answered in direct mail to Dragan, but I found it hard to find the answer, so here again: Explicitly add CoreData.framework in the "Link Binary With Libraries" section in the Build Phases tab of the target.