I'm going to switch to Linux with my new computer. I've read something weird about Firefox not supporting Flash on Linux (Chrome seems to support it, but I wouldn't want to switch if possible). The only sites I remember that I visit that use Flash are Youtube (with which I have no problem because I suppose it'll work fine with HTML5 (it'll work even better, because now with flash player I can't use the HTML5-only half speed configuration) and minigame sites (which I suppose it won't work anymore, but that's no big deal).
However, will this affect other sites I can't remember now? Just to be sure, is there any good alternative? (I've heard about Lightspark and Gnash, but they say that they aren't very good).