Dear Andrew,
as you say, the Unicode representations of upadhmānīya and jihvāmūlīya are not combining characters. As far as I know we have to live with that, so if by implementing them correctly you mean combining with the next akṣara, then I don't think it can be done in a Unicode environment. If all you need is _some_ acceptable rendition, then Tiro Devanagari Sanskrit may be a good font choice. Here's a page that tells you which fonts include these characters and how they look:
jihvāmūlīya https://graphemica.com/%E1%B3%B5/glyphs
upadhmānīya https://graphemica.com/%E1%B3%B6/glyphs
As to retaining them in your edition, I'm sure you've already considered that a combining upadhmānīya/jihvāmūlīya can give rise to corruption/variants different from those that might arise from a visarga. So even if the Devanagari rendition is non-combining, using these characters in the edition can indicate to the end user that the Śāradā does not have a visarga here, and that may be helpful.
Dan

On Sat, 8 Nov 2025 at 01:11, Andrew Ollett via INDOLOGY <indology@list.indology.info> wrote:
Dear colleagues,

I am working with a manuscript that uses upadhmānīya and jihvāmūlīya for visarga before p/ph and k/kh respectively:

Screenshot From 2025-11-07 13-30-45.png
Screenshot From 2025-11-07 13-27-24.png

The script is Śāradā, but I was wondering (a) whether these letters are used in printed Devanagari texts at all recently and what their forms are, and (b) whether anyone can suggest a Devanagari font that implements them correctly. I am wondering whether it might be worthwhile to retain these signs in a (Devanagari) edition of the text, or whether I should just regularize them to visarga. (The codepoints are in the Vedic Extensions Unicode block, although unlike the codepoint for visarga, they are not combining characters.)
Andrew

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