Que? No habla firefox.
It may be necessary to reinstall the programs in question.
I don't know if WM10 would play nice with FF. Reloading it would be the test, I guess. You won't beable to use WM imbedded in the FF browser, just download the file in question and watch it in the standalone player if possible.
PealPlayer should be fine with some tinkering or a complete re-install...