back in 9d9aed39 (use <a id=""> instead of name, as name is not HTML5,
2023-06-01) we switched everything to id= but overlooked that id=
actually gets redacted by GitLab's sanitizer. With this, we should be
able to get the anchors through the filter even if it generates
non-conformant HTML5.

howto/git.md

@@ -240,7 +240,7 @@ Changes to most repositories are reported to:
 
  * Some repositories have a dedicated mailing list for commits at https://lists.torproject.org
 
-<a id="how-to-migrate-a-git-repository-from-legacy-to-gitlab"></a>
+<a name="how-to-migrate-a-git-repository-from-legacy-to-gitlab"></a>
 ## Migrating a repository to GitLab
 
 Moving a repository from Gitolite to GitLab proceeds in two parts. One