There is clearly a need for a generic solution to hash fragment
routing in MediaWiki.
So far I've seen needs in MultimediaViewer, Kartographer,
MobileFrontend, Gather and potential needs in VisualEditor. There are
probably other bespoke solutions in other extensions too.
It would be great to take a minute and standardise on something (we
can always change it later).
I invite your discussion here:
https://phabricator.wikimedia.org/T114007
and your thoughts on my straw man proposal:
https://gerrit.wikimedia.org/r/#/c/260950/4