<http://www.unicode.org/reports/tr51/tr51-8.html#Emoji_Implementation_Notes>
> … including the user of … Should be just “use”. > * emoji zwj sequence > - may have an emoji variation selector. > - should be displayed with an emoji presentation by default, even when an > emoji zwj element is a singleton with Emoji_Presentation=No. “zwj” should be “ZWJ” in all instances, also found elsewhere. If I don’t misread, this seems to be saying nothing about a (hypothetical) emoji ZWJ sequence consisting of 2 or more elements with `Emoji_Presentation=No` without any VS-16. What’s the actual intention? 1. If there’s any VS-16 or any character with `Emoji_Presentation=Yes` in a ZWJ sequence, the whole sequence SHOULD be treated as emoji(s). 2. A ZWJ sequence SHOULD be treated as emoji(s) if it contains only characters that either have `Emoji_Presentation=Yes` or whose glyph *can* be affected by VS-16. Only #2 would cover a ZWJ sequence of `Emoji_Presentation=No` characters without any VS-16 stuck on them.
