Creating this task based on the discussion of the parent. We should figure out which WIki's are good candidates and start conversations for getting the extension deployed.
Some suggestions from @Tgr:
If we want to speed things up (e.g. start testing sooner), we can probably deploy to some or all of the non-community wikis (testwiki, foundationwiki, wikitech, mediawikiwiki) without waiting for the blockers.
And @Johan had some suggestions on where to announce:
wikitech-l rather than wikitech-ambassadors-l, I'd say, they're more of the target audience for mediawiki.org and Wikitech. Possibly a mention in Tech News, to tell people there's a place we're testing this, and because people like to be able to keep tabs on future development of something before it hits their wiki.
Work with local communities to enable TemplateStyles on non-content project wikis. Let the community know how the feature works, reference documentation, and let folks know where to get help.
List of wikis to include (probably incomplete, please help clarify):
- Test wiki (test.wikipedia.org)
- Wikitech (wikitech.wikimedia.org)
 Meta wiki
 Wikimedia Foundation wiki
Q2 (Oct-Dec 2017)