Long-term prevention for T263866: 1.31.10 patching issues. Patch files may seem antiquated but given the number of reports we get when something goes wrong, they're definitely actively used.
The tool would fetch the original tarball for a release, 1.31.0, then apply all the patches on top of each other, 1.31.1, 1.31.2, etc. to ensure there are no conflicts. It would then move on to using the 1.31.1 tarball as a base, and then apply 1.31.2, 1.31.3, etc.
It should be designed to support patch files that have been generated locally for an upcoming release, but not yet released/published.
I'm currently planning this as a standalone tool, but I think if it works and isn't unbearably slow, we should integrate it into makerelease2.py as part of the patch generation process.