If you launch a JUCE project, and just click on the Project Settings button to take a look, it will flag the file as “dirty” and needing to be saved. Later, you try to close and are presented with the Unsaved Changes warning dialog.
This is really annoying, since it leads to doubt as to whether you actually modified anything, and whether you want to save it if so.
Running JUCE 6.0.7 on Mac Mojave.