wikimedia/html-formatter uses loadHTML. It shouldn't. It should use Remex.
Maybe we should just remove the HTMLFormatter framework into Remex and remove uses of the library entirely from core.
Review of current usage: https://codesearch.wmcloud.org/search/?q=\bHtmlFormatter\\HtmlFormatter\b&files=php
- MobileFrontend – https://gerrit.wikimedia.org/r/c/mediawiki/extensions/MobileFrontend/+/1156787
- mediawiki/core WikiTextStructure (used by CirrusSearch) – https://gerrit.wikimedia.org/r/c/mediawiki/core/+/1174812
- mediawiki/core several tests for HTML outputs of special pages – https://gerrit.wikimedia.org/r/c/mediawiki/core/+/1169784
- IPInfo – https://gerrit.wikimedia.org/r/c/mediawiki/extensions/IPInfo/+/1170539
- LinkTarget (non-WMF) – https://gerrit.wikimedia.org/r/c/mediawiki/extensions/LinkTarget/+/1169787
- TextExtracts – https://gerrit.wikimedia.org/r/c/mediawiki/extensions/TextExtracts/+/1170561
- Citizen (skin, non-WMF)