Newly inserted "blocked" <base> elements would not result in an update to the document base URL, which does not match the standard.
<rdar://problem/114756660>
Pull request: https://github.com/WebKit/WebKit/pull/17285
Committed 267498@main (94fe30e306b5): <https://commits.webkit.org/267498@main> Reviewed commits have been landed. Closing PR #17285 and removing active labels.