Is it guaranteed that contexts will always be lost at the same time?  I thought that there were some devices where we were limited to 2 webgl contexts at once.  Doesn't creating an extra webgl canvas here use up one of those precious contexts?

I basically don't understand webgl at all, so if this works, it seems like a great way to solve this problem. I just want to make sure that the assumption (that all webgl context will be lost at the same time) underlying it makes sense.