The special wikis are hardcoded:
https://github.com/wikimedia/InteractionTimeline/blob/master/src/utils/specialWikisList.js
which was done in response to T180087.

These should instead come from the site matrix:
https://meta.wikimedia.org/w/api.php?action=sitematrix&formatversion=2

This means we wont have to update them when they are updated by operations.

Since the hard coded list of special wikis is being appended to the standard list of wikis, I don't think it should be disruptive to append all of the special wikis to the end of the standard list.