It should still possible to fork Firefox and remove this requirement, right ?
Mozilla has said that this requirement is set by one flag at build time, so building a version without this requirement should not be any more difficult than just compiling Firefox I have never done that, but I think it's slightly non-trivial. The hardest part though would be distributing the fork though, so a Linux distribution like Debian mentioned this change as others have mentioned would be one way to build a popular fork without this requirement.