If you get an answer to the Safari question, please ping me. I’m interested in knowing also.
While I do not know about Mac OS compatibility, I believe that this one is browser dependent.
I found versions for Chrome and Firefox, showing the author’s preferences at the time it was written.
Not sure about Safari or other non-Chromium browsers, or about the entire Windows/Mac/M1 world.
Pinging some folks who should be able to shed light on the subject.