[hotfix] anchors do not count towards mixed content
[hotfix] anchors do not count towards mixed content

see https://bugzilla.mozilla.org/show_bug.cgi?id=928753
humphd/thimble.mozilla.org,mozilla/thimble.mozilla.org,humphd/thimble.mozilla.org,humphd/thimble.mozilla.org,humphd/thimble.mozilla.org,mozilla/thimble.mozilla.org,mozilla/thimble.mozilla.org,mozilla/thimble.mozilla.org