In article <CALp2H_3tLC71X6-jvH2XD-6qX8O=KE5wHa561QPk-w2OoCX9HA@mail.gmail.com>, Nima Aryan <nimawebgard@gmail.com> writes:

>    With ZWNJ-as-space, the Droid Sans problem (showing box) is resolved but
>    the Noto Sans still shows small superscript bar line (Arial is also have
>    similar problem).

I'm sorry.  The code for ZWNJ-as-space had a bug.  Please try the
attached new one.

Anyway, I also installed Nato Sans (i.e. NotoSans-Regular.ttf) by
"fonts-noto" debian package, but it seems that font does not support
Arabic.  If your "Noto Sans" font supports Arabic, please send me it.

>    With ZWNJ-absorb, I couldn’t find any problem with any font. As a user,
>    it seems perfect.

>    with ZWNJ-thin-width, also seems good and I couldn’t find any problem in
>    fonts.

With this method, if you are using the same "Noto Sans" font as mine,
you should see a visual glyph that "Noto Sans" defines for ZWNJ.

---
K. Handa
handa@gnu.org