IMSC1 Comments

   - where is #image feature defined? it is referenced twice without any
   referent
   - why is #nested-span prohibited on image profile when #content span is
   already prohibited?
   - #lineBreak-uax14 is never 'used' by a document? it is either
   implemented or not implemented by a presentation processor; so it doesn't
   make sense to cite as MAY be used or SHALL NOT be used; it would, OTOH, be
   appropriate to require an implementation of the text profile to implement
   this feature;
   - excluding #bidi and #direction on image profile is inconsistent, since
   #bidi includes #direction, #unicodeBidi and #writingMode-horizontal; better
   to exclude #direction and #unicodeBidi, but retain #writingMode-horizontal
   with lrtb or lr values;