Diacritical marks differences are not shown in a way that is identifiable
Consider the following text: عَن ابْنِ شِهَابٍ أَنَّ عُمَرَ بْنَ عَبْدِ الْعَزِيزِ
if I were to remove the first diacritical mark on the first letter like so: عن ابْنِ شِهَابٍ أَنَّ عُمَرَ بْنَ عَبْدِ الْعَزِيزِ
and then compare the two texts in meldmerge, I see the following:
As you can see, while meldmerge highlights the entire text to show there a difference does exist somewhere, it does not show exactly where that difference is.
This is true even on long texts that have diacritics, the whole text gets highlighted:
I also tested this with other languages that use diacritics, and get the same result. Text used: އެއް ދުވަހަކު ޢުމަރު ބްނު ޢަބްދުލް ޢަޒީޒު ނަމާދު ފަސްކޮށްލެއްވިއެވެ. Diacritic change: އއް ދުވަހަކު ޢުމަރު ބްނު ޢަބްދުލް ޢަޒީޒު ނަމާދު ފަސްކޮށްލެއްވިއެވެ.