You are correct, I had to remove webkit2gtk4.0 and webkit2gtk4.0-devel.x86_64. After doing so, the upgrade went through fine, and then I reinstalled webkit2gtk4.0 since 3d printer slicing software (Orca and Qidi Slicer) do not work without it.
Question: does rpm-ostree reset also remove local packages, or just the layered ones?
I’m pretty sure it removes everything. Yeah you may have to do that each time webkitgtk revs in the repo, but I’m not sure, just something to check on every once in a while.