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You are correct in this that such words should not be something a child needs to hear.
If possible, the best thing to do is to confront your ex when your daughter is not present.
If you share custody, it would be difficult to put stipulations on the visitations contract.
Perhaps you can tell your ex that this kind of language can be damaging to a child and that it is not a healthy thing to display one's frustrations in the present of the child. Point out to her that those words are only hurting your daughter. If your daughter is older enough she can tell her mom that this hurts her and she does not wishes to hear it.