Reintroduce a mechanism to enable features from WebKitAdditions, which was removed in https://trac.webkit.org/changeset/218433/webkit. Also, introduce a new EXTRA_ZOOM_MODE feature flag.
Created attachment 331890 [details] Patch
<rdar://problem/36717545>
<rdar://problem/36717546>
Comment on attachment 331890 [details] Patch Thanks for the review!
Comment on attachment 331890 [details] Patch Clearing flags on attachment: 331890 Committed r227281: <https://trac.webkit.org/changeset/227281>
All reviewed patches have been landed. Closing bug.