On Wed Dec 10 18:24:34 2025 +0000, Jade Pfeiffer wrote:
On testing, these fonts cannot be previewed or installed on Windows 10, with an error of "The file '[filename here]' does not appear to be a valid font." They're `.otf`, which is still supported according to Microsoft Support docs, while the base font MaterialIcons-Regular is `.ttf`. The unique name field isn't shown anywhere in font selection (for notepad) or file properties, otherwise it would show as "FontForge 2.0 : Material Icons : 5-3-2019" in any menus. They are provided by the `material-icons-fonts` package in Fedora. That's reasonable, I was following that because the code was using UniqueID for `otmpFullName` that another unique signature would be necessary. Microsoft's OpenType docs[^1] do not give that much information on that name table value, only stating that is it a unique value for applications to identify the font being used, giving no other fallback information for if this field is missing. Otherwise If it should properly be a Full Name (and human readable), it could be constructed[^2] using 1 (Family) and 2 (Style) based on the examples[^3] given in Microsoft's OpenType docs. [^1]: https://learn.microsoft.com/en-us/typography/opentype/spec/name [^2]: https://learn.microsoft.com/en-us/typography/opentype/spec/recom#name [^3]: https://learn.microsoft.com/en-us/typography/opentype/spec/namesmp Ok, I see I confused otmpFullName with otmpFamilyName. Yes, unique name is not something for end user to see in a font selection list. It's true that some fonts do not install with font installation utility on Windows, it's not about otf vs ttf, but about missing things that wellformed font should have on Windows. Sometimes it's possible to add such fonts manually to windows/fonts, then to the registry, reboot, and use them.
I don't actually know what Windows is using for otmpFullName on Windows, for the fonts that could be installed. -- https://gitlab.winehq.org/wine/wine/-/merge_requests/9744#note_125402