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Firefox Quantum hide text when it doesn't support its font

  • 5 replies
  • 1 has this problem
  • 2 views
  • Last reply by cor-el

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I just updated to firefox quantum on my ubuntu pc. When it doesn't recognize the text font, it just hide it... Here is a screenshot of messenger.com: https://screenshots.firefox.com/jUwDpE7Xj1GNmMRp/www.messenger.com But when I change font-family from css (using "inspect element") it's working properly. On my windows pc I doesn't face any similar issue. Is it a bug or I have to change something on my preferences?

I just updated to firefox quantum on my ubuntu pc. When it doesn't recognize the text font, it just hide it... Here is a screenshot of messenger.com: https://screenshots.firefox.com/jUwDpE7Xj1GNmMRp/www.messenger.com But when I change font-family from css (using "inspect element") it's working properly. On my windows pc I doesn't face any similar issue. Is it a bug or I have to change something on my preferences?

All Replies (5)

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Also I already tried to disable all of my extension, but the issue remains the same.

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You can check for sandbox security related issues.

You can set this pref to 2 or 1 on the about:config page to lower the sandbox security setting.

  • security.sandbox.content.level = 1
  • close and restart Firefox to make the change effective.

If '1' still doesn't have effect then try '0' to disable the sandbox.

If this didn't work then undo/reverse the change and reset the pref via the right-click context menu to the default value.

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

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Note that you should check the Fonts tab in the Inspector in such cases to see what font Firefox tries to use.

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Thank you cor-el for your response. I tried your suggestion changing sandbox security level to both 1 and 0, but it didn't have any effect.

What I finally did is to uncheck the "Allow page to load their own fonts, instead..." on the "Advance" option of Fonts & Colors under about:preferences.

Now firefox loads websites fonts normally for some reason (I thought it would load them all according to my selection) and in any other case it uses dejavu font-family.

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What font did Firefox try to use if you check this in the Fonts tab?

You can check gfx.downloadable_fonts.enabled on the about:config page and make sure it is set to true (if necessary double-click the line to toggle its value to true).