Today I tried to ask a question with tag regex and got rejected with:
Oops! Your question couldn't be submitted because:
Creating the new tag [regular-expressions] is not allowed since the tag [regular-expression] already exists. If you think this new tag should be allowed, raise it on meta.
I didn't type "regular-expressions" so I assumed that "regex" was aliased to it, before it became outdated/superceded by "regular-expression".
The regular-expressions tag actually does exist, but something's wrong; I can't get to its synonym list (but I see the regex synonym in the master list), and your new question tried to create it, so apparently some parts of the system don't see it. I'm going to wait for a dev to look at this before I fix the synonym and merge them
Can't repro: tagging with regex now automatically retags with regular-expression (singular). regular-expressions is an unused tag (a part from one test I made that will go away very soon).
