Is the comment re. unstable-book in `src/libsyntax/feature_gate/active.rs` still relevant?

[Centril]

See #63824 (comment).

The comment currently exists in src/libsyntax/feature_gate.rs but is being moved in the PR above to src/libsyntax/feature_gate/active.rs.

cc @oli-obk

[est31]

unstable-book-gen at least uses tidy which seems to have been updated by 3cfb6bc

So any autogenerated unstable book page won't need any updates. Any non-autogenerated page will need one though as the tracking issue is hardcoded there. Changes that aren't detected automatically are for example when the tracking issue changes and the entry in the book is not updated. When the feature stabilizes, there is a tidy error though. So yes, active is a good place for that comment.

[Centril]

@oli-obk Seems the answer is "yes". I'll close this for now.