If you ever had to deal with DOMPdf rendering from rich text editors, tgis is likely useful for you.
https://helgesver.re/articles/why-combining-marks-break-in-dompdf
Helge SverreWhy combining marks break in DomPDF - Helge SverreNon-shaping PDF engines like DomPDF render combining marks as separate glyphs. Norwegian å becomes 'a' plus a drifting ring. The fix: two passes of Unicode normalization, plus a Latin-script lookbehind regex so the same fix doesn't strip Arabic, Hebrew, Hindi, or Thai marks.
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