Instead of accessing line boxes directly.
Created attachment 379733 [details] patch
Created attachment 379827 [details] wip
Created attachment 379830 [details] patch
Created attachment 379831 [details] patch
Created attachment 379832 [details] patch
Created attachment 379834 [details] patch
Comment on attachment 379834 [details] patch Clearing flags on attachment: 379834 Committed r250519: <https://trac.webkit.org/changeset/250519>
All reviewed patches have been landed. Closing bug.
<rdar://problem/55841808>