On 13 Apr 2020 09:23 -0400, from cym224 at gmail.com (Nemo):
> For zeroes and oscars, I dimly recall -- or possibly hallucinate --
> that some primeval standard specified putting a tail on oscar and
> leaving zero alone.  A bit of searching turned up nothing, though.

The original Palm Pilot "Graffiti" alphabet, designed to use
single-stroke for all unaccented characters, had O (oh) and 0 (zero)
both as plain circles drawn counterclockwise starting at the top
(separated into different drawing areas so the OS would know which you
intended), but Q was drawn as an O with a short tail to the right at
the end.

Might that possibly be what you're recalling?

https://en.wikipedia.org/wiki/Graffiti_(Palm_OS)

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