Creator does not see missing .qbs files after they appear

I checked out out a project with git and opened its main .qbs file. It turned out that some of the .qbs files were in submodules, so opening the project failed (partially).

I checked out the git submodules, but Creator still gave the same warnings about being unable to open the .qbs files in the submodules. Closing the project and reopening did not help.

Removing the build directory and then opening the project again worked as expected.