Implement <exclusion onpage> or another way to disable rulesets per DOM root origin
In this thread, I proposed a new type of ruleset exclusion , that would allow rulesets that affect 3rd party stuff (video players, CDNs, etc) to be disbaled only on pages where they are used in a weird way that causes breakage.
This has some disadvantages (it will mess with proxy ports of HTTPS Everywhere) but it's probably worthwhile anyway.