I didn't really mean legislation--just strong grassroots demand. These are corporations, and they'll build the features their customers want, after all.

Maybe we just need a a Kickstarter to pay for the engineering time required to get this coded into Firefox and Chromium. If Mozilla or Google don't like it, call the result a fork and start a campaign for people to switch, as happened with OpenOffice+LibreOffice, or with MariaDB. Of course, I think both Google and Mozilla are smart enough that they'd see what was happening there, and just adopt the open blacklists.

As browser-users, I believe that we really do have the ability to affect the decisions of these companies, if we have something we can all get behind. :)

(...at least, if it doesn't directly interfere with their bottom line, like including an ad-blocker in Chrome would for Google. Can't have everything.)