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How to use custom system fonts on Firefox Developer?

  • 4 replies
  • 1 has this problem
  • 3 views
  • Last reply by cor-el

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Hello there,

I've recently switched from Firefox to Firefox Developer. I've noticed that while in FF, I am able to change the default fonts (such as San-Serif font to Inter, and Monospace font to Monaco), but in FF Developer, I am unable to change the fonts to anything but the defaults. Can someone help me fix this issue, or is this issue a feature of FF Developer edition?

Thanks a lot, dodeca12

Hello there, I've recently switched from Firefox to Firefox Developer. I've noticed that while in FF, I am able to change the default fonts (such as San-Serif font to Inter, and Monospace font to Monaco), but in FF Developer, I am unable to change the fonts to anything but the defaults. Can someone help me fix this issue, or is this issue a feature of FF Developer edition? Thanks a lot, dodeca12
Attached screenshots

Modified by dodeca12

All Replies (4)

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Gahh I messed up typing this, please disregard.

Modified by dodeca12

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Do you at least see the fonts list when you click the down arrow ?


Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window

See also:

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Hello there,

Firstly thanks a lot for your reply. After following your instructions, I still am not able to choose my preferred fonts :( I am unable to even see the installed system fonts on Firefox Developer.

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You can create a new profile as a quick test to see if your current profile is causing the problem.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.