[ttml2] Pull Request: clarify use of tts:textCombine

cconcolato has just submitted a new pull request for https://github.com/w3c/ttml2:

== clarify use of tts:textCombine ==
closes #278

See https://github.com/w3c/ttml2/pull/619

Received on Wednesday, 31 January 2018 19:53:02 UTC