In reply to https://boffosocko.com/2020/12/24/55784090/.
Apparently, a similar “share button” for Mastodon did exist before it got removed again (https://github.com/tootsuite/mastodon/pull/8127). It’s Mastodon’s decentralized nature that makes things so complicated: there simply isn’t a single URL to point to. That said, there seems to be this alternative JS library (https://aly-ve.github.io/Mastodon-share-button/) that may just work.
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