It sounds like you're referring to MemoServ. This requires both parties to have an account on the server, and a separate private message to a dedicated bot.
What was being described was more like saving a highlight; with much less friction. On Discord, I can @someone even if they're a nickname-only user with no account.
What was being described was more like saving a highlight; with much less friction. On Discord, I can @someone even if they're a nickname-only user with no account.