Feels GREAT! Happy to be using this in addition to Safari. I also added uBlock Origin as an adblocker but would still love if FF eventually included native, declarative content blocking like Safari (probably less likely given how much money they get from Google).
I don’t want necessarily want an adblocker built into my web browser. It creates too much centralized risk and power for the kinds of shenanigans pulled by ABP or ghostery, and it would hurt adoption of good add-ons like ublock.
What I DO want to see is something like ublock matrix become a standard feature. Matrix is an incredible add-on that has made the web more useable and more debuggable for me. If it was built-in, the defaults would have to be toned-down or turned off, because it breaks too much of the web, but a simple “privacy mode” toggle to step up restrictions would be welcome in a private browsing window.
Call it “War Mode” or “Paranoid Window” when using a private window with maxed out Matrix.
It's not an adblocker. It's a "content blocking" engine. Basically, there are two pieces to any blocker: the blacklist, and the actual execution (matching against blacklist rules, and probably executing JS to remove it).
Safari's got a native engine for the execution part. And you pass in the blacklist with declarative rules. It's the best of both worlds in that you get competing blacklists, but the actual engine is even faster than JS. And for security like you said, there aren't any shenanigans since it's literally a JSON blacklist and can't contain code.
Firefox includes Tracking Protection, which, as it says on the tin, blocks trackers, not ads. But many, many ads have trackers built in, so it practically also blocks most ads.
This is default-enabled in Private Browsing. To enable it in normal browsing, you can toggle privacy.trackingprotection.enabled in about:config. I think, there's also now a GUI toggle in the settings to do that, I haven't checked yet.
And well, the main-motivation for not default-enabling it is not some Google-conspiracy, it's because they'd take away the income source of many webpage owners who in turn would simply stop testing against Firefox, if not block it completely.
Apple doesn't have to give as much of a fuck about this, as they have basically guaranteed market share with macOS and iOS, and because Chrome uses a fork of their browser engine, so if webdevs test against Chrome, it'll almost certainly also work in Safari.
