I don't think fighting a monoculture is a bad thing. Monoculture is bad in the long run, there are several implications to it mostly security wise. So its not

I don't think fighting a monoculture is a bad thing. Monoculture is bad in the long run, there are several implications to it mostly security wise. So its not just monoculture. It's also Mozilla's wast ecosystem of customization and the good will it's projects generate. Look at it this way - Did Chrome made/sponsor PDF reader in JS? Did it sponsor a Flash VM in JS? Did Google Chrome team made tools other than would help all vendors equally? Dart and NaCl are valiant efforts but they help Chrome first and other browsers second.