I haven’t found this feature anywhere. It’s often used on reddit to make sure a post’s content doesn’t disappear if a subreddit gets removed or is shut down for some reason. (edit: or recently wasn’t accessible because a subreddit went private in protest or otherwise. Or, more normally, you want a single content page to share in multiple communities for easier edits to one source, etc.) You just post a link to the original. The only thing I can think of to do it here (or on a different instance) is create a community that only myself can post to as a mod, but unsure if such a thing is frowned upon.
We are happy for anyone to create communities on Reddthat.
As long as we don’t have to step in due to any “dubiousness” or stupid amounts of reports we will allow most communities.
Lemmy doesn’t have that feature as content is more around communities, where as mastodon is more focused on people. It might come in the future, but that’s more 2024+ at this point.
Oh, I would thoroughly expect you to ban such a community if it became a staging area for trolling and abuse. That’s one reason I’m here, getting away from that nonsense. My intention is just having a central place for content that is too long for mastodon, and/or that I could share in communities, or link to from mastodon (or outside the fediverse in general.)
edit: and thank you for answering the question, appreciate knowing I can make such a thing here.