I think OP wants to aggregate certain topics on the same feed. For example, there are a couple of technology communities across different instances, with a custom feed you could have everything in one place.
It kinda works on the subscribed feed, but you just have everything instead of specific topics.
I wouldn’t even go that far to be honest.
server
“wtf is this”?
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I’m cheap and like free shit
If I understood it correctly, it’s when previewing the comment/post, not when viewing an already made comment/post.