She is actually past probation. It's a unionised job. She's now almost impossible to get rid of.
Her behavior is your solution.
You don't do things that make her flip her shit on purpose? Start doing it.
Make her flip her shit while remaining your calm, precise, well doing your job self. You're not to blame. Her overreacting will be too much on their nerves one day, they will let her go for it, and on the side or silently thank you for helping them get rid of her.