Arabic RTL fonts do not reneder

When writing Arabic font, the editor writes the words correctly, however, once you click outside, the words break up into boxed X's.

However, when scrolling through the fonts I was able to find some fonts that render the words correctly.

**### Writing**

**### Rendered**

Start by reproducing the issue in the editor with Arabic text, comparing the writing state with the rendered state after clicking outside. Trace the font rendering path and compare fonts that render Arabic correctly with those that produce boxed Xs. Done means Arabic text renders correctly after leaving the text editor without regressing working fonts.

Written by the indexing model from the issue text.