[ttml2] Profiles cannot permit `xml:base` on `ttp:features` while prohibiting `xml:base` elsewhere

palemieux has just created a new issue for https://github.com/w3c/ttml2:

== Profiles cannot permit `xml:base` on `ttp:features` while prohibiting `xml:base` elsewhere ==
In TTML2, both `#base` and `#base-version-2` imply support for `xml:base` on `ttp:features`.

It is therefore not possible for a profile of TTML2 to match TTML1, and allow `xml:base` on `ttp:features` while disallowing `xml:base` elsewhere.

Suggest excluding `xml:base` on `ttp:features` and `ttp:extensions` from `#base-version-2`.

Please view or discuss this issue at https://github.com/w3c/ttml2/issues/834 using your GitHub account

Received on Saturday, 16 June 2018 03:57:16 UTC