Needs Support for signed 64-bit browser window dimensions.

[lfricken]

For complicated reasons I won't get into, I'm trying to make a website with this embedded, but when trying to make either of the browser window dimensions either above around 4 billion pixels wide, or negative, it crashes. I tracked this down to the fact that its using unsigned 32-bit integers for window dimensions. This can be solved by upgrading to signed 64 bit integer, which makes the limit high and low enough (for me at least). I would recommend two 256 bit ints to cover things into the near future, like Windows 12 support.