Noto Sans Mono is not detected as monospace font by Fontconfig

[chiak597]

Defect Report

Title

Noto Sans Mono is not detected as monospace font by Fontconfig

Font

NotoSansMono-Regular.ttf (affects all variants of Noto Sans Mono)

Where the font came from, and when

Site: https://github.com/notofonts/latin-greek-cyrillic/releases/download/NotoSansMono-v2.010/NotoSansMono-v2.010.zip
Date: 2022-08-04

Font Version

2,01

OS name and version

Debian SID

Issue

Fontconfig cannot detect Noto Sans Mono as a monospace font. Also Font Viewer app says that font has "proportional" spacing instead of "monospace" (see screenshot). Because of that, this font cannot be used in applications accepting only monospace font (for example Linux terminal emulators).

As stated in https://www.freedesktop.org/software/fontconfig/fontconfig-user.html, fontconfig uses "spacing=100" property for matching monospace fonts and Noto Sans Mono is missing that property.

$ fc-scan static/NotoSansMono/NotoSansMono-Regular.ttf | grep spacing
$

I unpacked legacy Noto Mono font from the Debian package and that one contains required property and also can be used as a monospace font.

$ fc-scan NotoMono-Regular.ttf  | grep spacing
	spacing: 100(i)(s)
$

Screenshot