The symptoms of my problem match this question pretty much exactly: Changed static files are cropped/padded to the new size and served the old - Fedora
Whenever I ma
In the end it turned out that this was probably being caused by VM issues. The code in question was located on a Windows drive, but was being served from within a Linux VM that was accessing the code via a shared directory. Remounting the share seemed to fix the problem (although not necessarily reliably).