Just FYI.
As ETA for this work:
https://phabricator.wikimedia.org/T128173
cannot be even estimated, we have utilized in pl.wikisource the old
Swedish solution (by Innocent bystander) for providing interwikis based
on the work/edition Wikidata model.
This is a modified sv.ws solution with
ankry.wiki, 04/11/2018 02:42:
We have restored in plwikisource the old, fast, light and efficient
toolbar as a gadget:
https://imgur.com/a/DFVhaeu
Thanks for sharing. Direct link for those who don't run proprietary
javascript:
https://i.imgur.com/VkeebIb.jpg
Federico