visually empty runs are ignored and should not be merged.
<rdar://problem/56769334>
Created attachment 382416 [details] Patch
Created attachment 382421 [details] Patch
Created attachment 382461 [details] Patch
Comment on attachment 382461 [details] Patch Clearing flags on attachment: 382461 Committed r251848: <https://trac.webkit.org/changeset/251848>
All reviewed patches have been landed. Closing bug.