Hi Robin E,
Thanks for taking the time to report this and for the very clear technical description of what you’re seeing.
According to the Unicode Standard, U+2173 (ⅳ) and U+2178 (ⅸ) are distinct code points with different definitions and numeric values in the Number Forms block (U+2150–U+218F): The Unicode Standard, Version 15 (Disclaimer: The Unicode Consortium website is a third‑party resource and is not operated or maintained by Microsoft. Microsoft does not control or endorse the content of external sites. The link is provided for reference to the official Unicode standard)
Microsoft’s official documentation for the Georgia font family describes supported scripts and general character coverage, but it does not specify rendering behavior for Roman numeral Unicode code points: Georgia font family
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Sign in with your Microsoft account and submit the report there.
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