Anchors on the samepage on course site not working

In Mediawiki - an anchor on the same page is specified as [[#Subheading|Foo]]

In the Wordpress snapshot an in page anchor is incorrectly linked back to the source anchor in the wiki.

See for example the Session link anchors here: https://wpms.oeru.org/lida101/course-guide/syllabus/

• Currently linking back to the main page https://wikieducator.org/#Session_1
• URL Should be: https://wpms.oeru.org/lida101/course-guide/syllabus/#Session_1

This one is urgent because it will break snapshots of existing courses.