openFrameworksLib.xcodeproj sometimes not expandable in XCode navigator

See this image

The /openFrameworks/openFrameworksLib.xcodeproj file to the left is expandable, the one to the right is not. This seems to switch back-and-forth arbitrarily. For example, the nav bar in the image became expandable after restarting XCode, having not changed anything. The other project’s nav remained un-expandable. Any rhyme or reason?

you can only have a project open once. so the first open project or the first project open after you close that one can open the OF library subproject, for the rest is locked and can’t be shown. thisi is a limitation in xcode, it tries to solce a problem in which you might try to compile a project twice simultaneously which could corrupt some files and we haven’t found any way around it

Ah that makes sense. Thanks.