Using PCRE2 10.43, the `\X` selector seems to capture more than one graphemes, as if does not break before the start of a new grapheme cluster. Regex: `\X` Input: `π³οΈβππ΄ββ οΈ` (`U+1F3F3 U+FE0F U+200D U+1F308` + `U+1F3F4 U+200D U+2620 U+FE0F`) When run, `\X` matches both flag graphemes: [Regex101 preview](https://regex101.com/r/pWL2Vr/1). Could you kindly shed me a light if I'm missing something? Thank you.