Documents in deeply-nested cross-origin browsing contexts could have obtained permissions granted to the top-level origin, bypassing the existing prompt and wrongfully inheriting the top-level permissions.
Documents in deeply-nested cross-origin browsing contexts could have obtained permissions granted to the top-level origin, bypassing the existing prompt and wrongfully inheriting the top-level permissions.
https://bugzilla.mozilla.org/show_bug.cgi?id=1755081