Through my investigation, this warning was thrown on new FontFace. Is it related to this

WFM on Windows 11 with Firefox nightly and Firefox ESR (128.11.0).
It's very likely an issue with the Windows font rendering backend.
Microsoft ended WIndows 7 support 5 years ago (https://learn.microsoft.com/en-us/lifecycle/products/windows-7) so we won't fix this issue.
FYI, the displayed warning in the console is unrelated to your issue.

WFM on Windows 11 with Firefox nightly and Firefox ESR (128.11.0). It's very likely an issue with the Windows font rendering backend. Microsoft ended WIndows 7 support 5 years ago (https://learn.microsoft.com/en-us/lifecycle/products/windows-7) so we won't fix this issue. FYI, the displayed warning in the console is unrelated to your issue.

Thank you for your reply. Could you please help me analyze where the problem lies? Thank you very much！
But if it is a problem of windows font，currently only PDf.js preview has problems. Under the same environment, it is normal to directly open the pdf preview with Google Chrome

Font issues are pretty hard to figure out especially when they're specific to an OS.
The fonts from the pdf are rewritten to make them suitable for the browser in fonts.js, so maybe there's something to tweak here.
The first thing you can try is to extract the font from the pdf (in using qpdf for example, take care the file you'll get can be compressed so you'd have to decompress it) then use ttx on it and try to see if there's something "unusual" or which looks suspicious. Once you find something which could be wrong, try to tweak it in fonts.js to see if it makes a difference (for example if a value is negative when it obviously must be positive, just try to clamp it or something like that before writing in the font data we'll pass to the browser).
Anyway, it's my way to fix this kind of bugs but maybe there's a better approach: I don't know.
I don't know what Chrome is using as a font backend on Windows.

Thank you very much. I'll give it a try

谢谢🤞