Development has stopped on the Safari extension due to the kneecapping of its capabilities in Mojave. Maybe the upcoming Chrome change will spark renewed interest in getting it to work to the extent possible.
Yes but as far as I understand it doesn't actually use the native API. The Content Blocker API has benefits from a performance and privacy perspective.
Yes, content blocker extensions are many times more lightweight than old-style blocker extensions (virtually zero negative impact on resource usage and site load speed), can never be hijacked to do anything malicious, and know nothing about you or your web traffic.
I use them on my iOS/macOS devices and the their effectiveness is quite apparent, especially on the iPhone where CPU and bandwidth aren’t as abundant.
