1. Open an existing file
2. Modify Album Artist, File Path will change (with default filenaming settings)
3. Double-click on File Path New value in Metadata Box, you can edit the value
4. When exiting the edit line, the value will be restored

Expected: since that's a read-only value, it shouldn't be possible to edit it at all.

If one selects Unclustered Files and come back to the field after step 2, edition isn't possible anymore (double-click will not enter in edit mode).