I tried to build my app with Xcode 15 and as part of that I changed the current project version and marketing version in the main app, but when I went to the various intent and watch extensions, the option to change the versions weren't there. I thought "hmm maybe Apple has gotten smart and just made those follow the main app" but I was wrong. The settings are still there but there is no UI to change them, and compiling now shows warnings about mismatched versions.
When I go into Build Settings and look for Versions, I can find the wrong values and change them there, but this is very laborious. Deleting the settings sets them to the default project versions, but there is no UI to set these either so nothing is changed and warnings still appear.
So for now I'm stuck with manually going to each build setting page and changing the versions there. Sigh. I think I'll file a bug report, this can't be right.
