We also include a temporarily fixed MuPDF file, before its official release: pdf-op-filter.c. This fix ensures correct handling of methods Page._cleanContent() and Annot._cleanContent().
We will take out this fix once MuPDF itself is rolled out with the correction.
People who cannot use one our wheels may copy this file into their MuPDF download before they generate it.
MuPDF's command line tools (mutool, mudraw, or muconvert) also contain this bug, which shows when options -s, -sanitize or -clean / -c are used. Re-Generating these tools with the fixed file will yield correct versions.