Components of subscript jña are positioned inconsistently

[dscorbett]

Fonts

NotoSansTelugu-Regular.otf
NotoSerifTelugu-Regular.otf

Where the fonts came from, and when

Site: https://github.com/notofonts/telugu/releases/tag/NotoSerifTelugu-v2.004
Site: https://github.com/notofonts/telugu/releases/tag/NotoSansTelugu-v2.004
Date: 2023-04-08

Font version

Version 2.004

Issue

Subscript jña was changed for #8 to be vertical instead of horizontal, but it is still horizontal before U+0C48 TELUGU VOWEL SIGN AI.

When a subscript jña precedes another subscript consonant in this font, the ña is below the ja and the other consonant is to the right of the ja. Other subscript sequences of two consonants are horizontal in this font. Why is subscript jña vertical? Unlike in other Indic scripts, it doesn’t have an akhand (atomic) conjunct glyph, so why is its subscript exceptional? I have not found any other Telugu font that treats jña differently from other pairs of subscript consonants: they all make all subscript sequences consistently horizontal or vertical or diagonal.

Character data

ర్జ్ఞైర్జ్ఞ్ఴ
U+0C30 TELUGU LETTER RA
U+0C4D TELUGU SIGN VIRAMA
U+0C1C TELUGU LETTER JA
U+0C4D TELUGU SIGN VIRAMA
U+0C1E TELUGU LETTER NYA
U+0C48 TELUGU VOWEL SIGN AI
U+0C30 TELUGU LETTER RA
U+0C4D TELUGU SIGN VIRAMA
U+0C1C TELUGU LETTER JA
U+0C4D TELUGU SIGN VIRAMA
U+0C1E TELUGU LETTER NYA
U+0C4D TELUGU SIGN VIRAMA
U+0C34 TELUGU LETTER LLLA

Screenshots