Orthographic errors in Noto Sans CJK Simplified Chinese

[mrk-z]

We noticed some orthographic errors in the Simplified Chinese (SC) version of Noto Sans CJK.

Overall it seems that some Traditional Chinese (TC) or Japanese glyphs are included in the SC subset.

艹: In certain glyphs, the horizontal stroke separates into two.
In SC, the horizontal stroke is usually a continuous stroke. The two horizontal strokes is usually happens in TC.
Examples: 茠荁莁菗

山: In certain glyphs, the bottom of left vertical stroke extends below the horizontal stroke.
In SC, the bottom left corner is usually aligned. The extended left vertical stroke is usually seen in Japanese typefaces.
Examples: 圸杣乢

丰: In certain glyphs, the first horizontal stroke curves up.
In SC, the first horizontal stroke is usually completely horizontal. The curved stroke is usually seen in TC.
Examples: 玤垹

女: In certain glyphs, the end of the first diagonal stroke extends over the beginning of the 丶 stroke
In SC, the two strokes of 𡿨 is usually aligned. The extended first stroke is usually seen in Japanese.
Examples: 嬶娯婲娿

月: In certain glyphs, the middle strokes are diagonal.
In SC, the middle strokes are usually horizontal. The diagonal strokes are usually seen in TC or Japanese
Examples: 脪臐胣腖

(for 胣, the 也 part also has a form usually found in TC.)

[NightFurySL2001]

Note that the project only has a limited coverage outside of GB2312, GB12345 and 通用规范汉字表 for Simplified Chinese. Quote:

Since GB 18030 isn't a glyph standard you can't really say anything is not "GB compliant". I'm not opposed to having a note somewhere, but I wouldn't call it a known issue or an issue at all. It's just a statement of clarification that not all glyphs follow PRC representative glyph conventions.

Originally posted by @punchcutter in adobe-fonts/source-han-sans#412 (comment)

Noted 3 characters are in 通用规范汉字表, which had been reported in adobe-fonts/source-han-sans#313, adobe-fonts/source-han-sans#324 and adobe-fonts/source-han-sans#206 (comment)

A few others are mentioned here:

These glyphs only have a TW form right now and no current plan to add a CN glyph without some compelling argument.

Originally posted by @punchcutter in adobe-fonts/source-han-serif#200 (comment)

You can see the glyph sharing status with my tool: https://nightfurysl2001.github.io/shs-cid/