It should be possible to remove a <track> from a <video> element and add it to back again.
<rdar://problem/14191593>
<rdar://problem/14211043>
Created attachment 205045 [details] Proposed patch
Comment on attachment 205045 [details] Proposed patch Clearing flags on attachment: 205045 Committed r151796: <http://trac.webkit.org/changeset/151796>
All reviewed patches have been landed. Closing bug.