I am testing an editor written in tkinter and have noticed some strange behavior. I am using the editor to test the Arabic script which also has composite Glyphs. I have noticed that when I move the cursor over a composite glyph, the glyph is temporarily split into its component glyphs. This can be seen in the two images I have attached to this question. Similar behavior is seen in an app made using PyQt. Notepad++ also does not move the cursor over the entire glyph, instead pausing in the middle of the glyph indicating that the glyph is composed of more than one character.