In Firefox 119 Fingerprinting protection has been added to Enhanced Tracking Protection in Strict/Custom mode (Suspected fingerprinters) what affects accessing local fonts. To include user installed fonts, modify this pref on the about:config page:

• about:config => privacy.fingerprintingProtection.overrides => -FontVisibilityBaseSystem,-FontVisibilityLangPack

You can open the about:config page via the location/address bar. On the warning page, click "Accept the Risk and Continue" to open about:config.

• https://support.mozilla.org/en-US/kb/about-config-editor-firefox

See also:

• https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop

Does it still happen if you disable Tracking Protection for the site?

Unfortunatelly after change in fingerprinting protection nothing happen.

Disable tracking protection not solve the problem too.

But i see the problem is mainly in google main sites or only few random websites. Most of other websites works correctly with fonts.

Try updating to version 121, it may have been fixed by Bug 1803406.

Wow, I didnt notice there is new update three days after updating to 120 :)

Everything now works ok. Thank You!