I shared a comment via the share option - to email the comment to myself for the morning. The URL was this:

https://lemmy.world/comment/2874575

But I’m getting an error and I think the problem is that the post/comment was on a different Lemmy instance other than .world?

I think perhaps the SHARE option needs to pay attention to the instance too? (instead of just appending lemmy.world/comment to the front of the comment ID)