Google also must share search data with competitors, but it's not totally clear what this is. The ruling mentions helping other engines with "long tail" queries.
All in all this seems like a pretty mild ruling, and an appeal can generally only help Google from a not to bad ruling at this point.
From what I understand Google could pay for Firefox to install a Google search extension, but they can't pay Firefox to make Google the default search engine. Even if they get google to pay for just pre-installing it, it's not going to be anywhere near what Google currently pays to be the default.
It seems to me that at very least Mozilla will have to renegotiate a contract and it's not clear what they might make off selling ads in that space. Google will presumably not value the lesser advantage as highly, but if the other provisions create more search engine competition there could be growing value to Mozilla in that ad real estate in theory