Remove broken bengali mono font name entry from 65-nonlatin.conf

( On Linux Mint 18)

$ fc-list :mono:lang=bn
/usr/share/fonts/truetype/fonts-beng-extra/mitra.ttf: Mitra Mono,\\u09ae\\u09bf\\u09a4\\u09cd\\u09b0:style=Regular

There seems to be only one mono font for Bengali language available which is Mitra Mono. But sadly this mono font cannot render Bangla(bn) correctly. Bangla is complex script font, for which there's currently no mono font available AFAIK.

The font itself is broken if I'm correct. It's listed as mono,serif,sans-serif. But ironically it can't show bangla correctly.

$ fc-list :sans | grep -i mitra && fc-list :serif | grep -i mitra && fc-list :mono | grep -i mitra
/usr/share/fonts/truetype/fonts-beng-extra/mitra.ttf: Mitra Mono,\\u09ae\\u09bf\\u09a4\\u09cd\\u09b0:style=Regular
/usr/share/fonts/truetype/fonts-beng-extra/mitra.ttf: Mitra Mono,\\u09ae\\u09bf\\u09a4\\u09cd\\u09b0:style=Regular
/usr/share/fonts/truetype/fonts-beng-extra/mitra.ttf: Mitra Mono,\\u09ae\\u09bf\\u09a4\\u09cd\\u09b0:style=Regular

Test file: nde.txt

This font has highest priority for bangla mono selection. For a system that has this installed, opening files in text editor looks like this:

This(above) is unreadable.

Above is "Noto Sans Bengali" which correctly shows Bangla.

So I'm requesting to remove https://gitlab.freedesktop.org/fontconfig/fontconfig/blob/master/conf.d/65-nonlatin.conf#L178 entry.

Without Mitra mono font Bangla shows with Lohit Bengali which has correct rendering.

There are at least three other fonts that can't show bangla correctly

1. Ani 2)FreeSans 3)FreeSerif

These 3 have problems with bangla ligatures.