Short term, we can work around the issue by either:

- Having the URL texture fade text using a grey gradient, to match the element it sits on (which is easy but problematic if we ever want to change the URL bar color on hover, etc)

- Write a shader that can fade portions of a quad according to a description.  Note that in this case, the gradient is not actually at the edge of the texture, since the URL texture currently houses text, icons and other things (this can only be split apart once we have a layout tool that can pack elements into a fixed space).