I exported to all platforms (excluding mobile) but it is kinda of a "use at your own risk"(still, better than no export at all) :D anyway, imo i value much more a dev that at least tries to make a game cross-platform than one that only makes it to one platform ;) (an example of this behaviour of mine is that i only spend my money on games that support linux)
EDIT: for me HTML5 works fine on firefox/linux
Anyway, good luck :)