A Visual Guide to Quranic Graphic Variants

While the text is the data, the graphic form is the text rendered as an image ‒ the text is basic, the graphic forms are just variants.
First different forms of ḍamma ‒ they are the same whatever Unicode says.

next different forms of sukūn:

in the middle you see an East African muṣḥaf in which fatḥa+sukūn when they follow each other are joined (as if one sign)







below nūn ṣīla (nūn quṭnī) by the same calli­grapher, Hafiz ʿUṯmān the Elder: whether the nūn is near the tan­wīn or below the alif does not matter, it is the same. Whether it has an extra kasra or not, either.