Follow up the discussion requested a new git for that extension at https://www.mediawiki.org/w/index.php?title=Git%2FNew_repositories%2FRequests%2FEntries&type=revision&diff=1851754&oldid=1850066
I requested a git by the original author (and some other users also) at https://www.mediawiki.org/wiki/User_talk:%D0%92%D0%BB%D0%B0%D0%B4%D0%B8%D0%BC%D0%B8%D1%80_%D0%A0%D0%B0%D0%B4%D1%83%D0%BB%D0%BE%D0%B2%D1%81%D0%BA%D0%B8#Git but sadly the progress is stalled although other promised. There are some github forks (e.g. https://github.com/dennisroczek/MW-MetaTitle and https://github.com/MageSlayer/MW-MetaTitle and https://github.com/JeroenDeDauw/AddMetaAndTitle - maybe more) and I do want to get them centralized here by the WMF. :-)
I'm willing to maintain the extension to keep it up to date as I'm one of the administrators at the libreoffice/The Document Foundation Wiki and we do use this extension.