Except if it's a compound emoji, which takes multiple codepoints -> more than 4 bytes.
So really the takeaway is that "character" is highly ambiguous nowadays and shouldn't be used anymore, use one of these instead:
* UTF-n code unit
* Unicode code point
* Grapheme Cluster
* Extended Grapheme Cluster
For the latter one also needs to specify the version of Unicode they're talking about, since every new compound emojis changes the definition of "Extended Grapheme Cluster".
