This is clearly a powerful feature, so it's a natural candidate for restriction. Chromium is restricting all of navigator.geolocation as of 50: https://codereview.chromium.org/1530403002/ Our telemetry shows that only ~0.1% of the usage of watchPosition() is in non-secure contexts. http://mzl.la/1VEBbZq That's low enough that we should go ahead and turn it off.

Is there any reason why we cannot limit getCurrentPosition() as well like Chromium? If not, this is a dup of Bug 1072859.

Posted the site compatibility doc: https://www.fxsitecompat.com/en-CA/docs/2016/use-of-geolocation-watchposition-will-be-limited-to-secure-sites/

getCurrentPosition() should also be limited.

Marking as DUP of #1072859: watchPositiong() and getCurrentPosition() should both be limited to secure contexts.