I am currently embedding custom emoji fonts via @font-face.
The approach works without fault in Anki Desktop, but fails in some cases in AnkiMobile.
Attempt 1
When using seguiemj.ttf, all emojis render correctly except composite emojis that use ZWJ or VS16 which instead fall back to default iPhone emojis.
Attempt 2
When using twemoji.mozilla.ttf, all emojis render correctly but VS16 gets rendered as a blank whitespace, which adds unwanted space after composite emojis that use it.
Color spill
In both cases, a line breaking after an emoji or a new line element after one that ended with an emoji will result in the text following it being rendered with the last color used to render the emoji.
I believe these could be Webkit isssues but wanted to confirm here before reaching out to them.
Thanks for the help!