jayvdb added a comment.
A few more public sites can be found at https://wikiapiary.com/wiki/Extension:Wikibase_Client , and a this query https://wikiapiary.com/w/index.php?title=Special%3AAsk&q=%5B%5BHas+extension%3A%3AExtension%3AWikibase+Client%5D%5D&po=%3FHas+website%3DWiki+name%0D%0A%3FHas+MediaWiki+version%3DMediaWiki+version%0D%0A%3FHas+extension+version%3DExtension+version%0D%0A&eq=yes&p%5Bformat%5D=table&sort%5B0%5D=Has+MediaWiki+version&order%5B0%5D=ASC&sort_num=&order_num=ASC&p%5Blimit%5D=500&p%5Boffset%5D=&p%5Blink%5D=all&p%5Bsort%5D=Has+MediaWiki+version&p%5Border%5D%5Bascending%5D=1&p%5Bheaders%5D=show&p%5Bmainlabel%5D=-&p%5Bintro%5D=%3Cb%3EThis+extension+is+in+use+on+the+following+websites%3A%3C%2Fb%3E%3Cbr+%2F%3E&p%5Boutro%5D=&p%5Bsearchlabel%5D=%E2%80%A6+further+results&p%5Bdefault%5D=This+extension+is+no+longer+in+use+on+any+website.&p%5Bclass%5D=sortable+wikitable+smwtable&eq=yes shows the sites with the lowest version first
Of those which are not using a wmf branch, they seem to all work for Wikibase Client 0.5+:
http://www.lycaeum.org/w/api.php?action=query&meta=wikibase&format=j...
clients connected to a repo on a different site:
http://wiki.geogebra.org/s/es/api.php?action=query&meta=wikibase&for... http://sv.pornopedia.com/w/api.php?action=query&meta=wikibase&format...
And a 0.3 client which doesnt support meta=wikibase
http://pwiki.ru/api.php?action=query&meta=wikibase&format=jsonfm http://pwiki.ru/api.php?action=query&meta=siteinfo&siprop=extensions...
TASK DETAIL https://phabricator.wikimedia.org/T85331
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To: jayvdb Cc: Aklapper, XZise, jayvdb, Pietrodn, pywikipedia-bugs