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Windows FontSubtitutes rules not being followed on Firefox 109.0b7

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Kotep
Kotep

I use the Windows registry FontSubstitutes (Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\FontSubstitutes) to replace system fonts like Segoe UI with other fonts. It takes a lot of work to get Windows itself to respect these options, to the extent that I have to make it believe Segoe UI isn't present by modifying a different registry location (Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Fonts).

However, Firefox does not respect the FontSubstitutes settings. Based on a previous post here, this is something it did prior to Firefox 89, but has stopped doing.

An ideal solution would be a way for Firefox to correctly read my FontSubstitutes settings. An acceptable workaround would be a way to provide Segoe UI for Firefox to use while still preventing its use in other applications. (I know that, for instance, Adobe Photoshop allows users to install fonts to Photoshop itself, bypassing the system fonts folder entirely.)

I use the Windows registry FontSubstitutes (Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\FontSubstitutes) to replace system fonts like Segoe UI with other fonts. It takes a lot of work to get Windows itself to respect these options, to the extent that I have to make it believe Segoe UI isn't present by modifying a different registry location (Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Fonts). However, Firefox does not respect the FontSubstitutes settings. Based on a previous post here, this is something it did prior to Firefox 89, but has stopped doing. An ideal solution would be a way for Firefox to correctly read my FontSubstitutes settings. An acceptable workaround would be a way to provide Segoe UI for Firefox to use while still preventing its use in other applications. (I know that, for instance, Adobe Photoshop allows users to install fonts to Photoshop itself, bypassing the system fonts folder entirely.)

Valittu ratkaisu

Could you try the workaround from back in the Firefox 89 days and let us know whether it still works:

https://support.mozilla.org/questions/1343838

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jscher2000 - Support Volunteer
jscher2000 - Support Volunteer

Valittu ratkaisu

Could you try the workaround from back in the Firefox 89 days and let us know whether it still works:

https://support.mozilla.org/questions/1343838

Kotep
Kotep Kysymyksen kysyjä

Thanks, setting gfx.windows-font-substitutes.always to true still works.