All working for me so far except for one problem: fragment IDs get don’t get handled right across the redirect; e.g., https://w3c.github.io/csswg-drafts/css-cascade-5/#layering ends up redirecting to https://drafts.csswg.org/css-cascade-5/#layering##layering — that is, the fragment part unexpectedly becomes #layering##layering.

I can look at the code myself this afternoon my time to try figure out why that’s happening, and patch it (if you don’t get to it first)