When asking a question on Meta, I've encountered a bug which consists in an error message saying that a moderator tag must be present. Here is an example:
Steps to reproduce this bug:
This isn't a big deal since it still allows posting the question without the moderator tag and doesn't allow posting it with the moderator tag, but I still think that this bug should be fixed.
PS: In case you're curious about how I noticed this bug, I usually put moderator tags (or untagged on non-meta sites) on my questions while I'm writing them so that I don't submit by mistake and then remove them when I'm ready to post.