When the line setting contains an optional alignment value, the cue is not rendered at the correct position, see https://w3c.github.io/webvtt/#webvtt-line-cue-setting.
Created attachment 351312 [details] Patch
rdar://problem/44384699
Comment on attachment 351312 [details] Patch Attachment 351312 [details] did not pass mac-wk2-ews (mac-wk2): Output: https://webkit-queues.webkit.org/results/9419303 New failing tests: media/track/track-cue-line-position.html
Created attachment 351326 [details] Archive of layout-test-results from ews105 for mac-sierra-wk2 The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews. Bot: ews105 Port: mac-sierra-wk2 Platform: Mac OS X 10.12.6
Comment on attachment 351312 [details] Patch Attachment 351312 [details] did not pass mac-ews (mac): Output: https://webkit-queues.webkit.org/results/9419729 New failing tests: media/track/track-cue-line-position.html
Created attachment 351332 [details] Archive of layout-test-results from ews100 for mac-sierra The attached test failures were seen while running run-webkit-tests on the mac-ews. Bot: ews100 Port: mac-sierra Platform: Mac OS X 10.12.6
Comment on attachment 351312 [details] Patch r=me once the bots are happy
Created attachment 351397 [details] Patch
Created attachment 351398 [details] Patch
Comment on attachment 351398 [details] Patch Thanks for reviewing!
Comment on attachment 351398 [details] Patch Clearing flags on attachment: 351398 Committed r236754: <https://trac.webkit.org/changeset/236754>
Landed: https://github.com/WebKit/WebKit/commit/0fcc46fa5d81f8572e9841ef88dcf81f59b39aba Marking this as 'RESOLVED FIXED'. Thanks!