python 3.8 looks to be still working for a bit yet (under cibuildwheel). Added migration guide - @kyamagu I think most of the still broken stuff are under skia.*ImageFilter . Anything else you feel like mentioning, or rewording?

I don't know why build_dir is docs/_build in setup.py, but docs/_build/html in the command line, but that seems to be correct and intentional. I have already pushed/published v87.9 proper (don't think there is anything you would mind), which triggered to online docs to revert back to the v87 version - which had a few *ImageFiler, and manually triggered rebuild docs on main to overwrite it without those missing *ImageFilter.

Thanks! Directly calling python setup.py is already deprecated, and I believe the update is correct. I don't quite remember the docs/_build/ path specification, but it's probably from the weird behavior of the setup hook.