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How do I adjust the font sizes in the firefox display?


I've gotten the font size of the tabs and menu bars and buttons too large, in both firefox and thunderbird, and can't figure how I did it or how to shrink them to the right size. This is not the websites I'm talkling about, but how the program displays are sized. I've gone over and over the menus and options and can't find the adjustments.

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Installed Plug-ins

  • This plugin provides integration with Cinnamon for live extension enabling and disabling. It can be used only by extensions.gnome.org
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  • User Agent: Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:17.0) Gecko/20100101 Firefox/17.0

More Information

Gingerbread Man
  • Top 25 Contributor
220 solutions 905 answers

The font style and size in the Firefox interface is controlled by your operating system.


  • Top 10 Contributor
  • Moderator
10742 solutions 96657 answers

Use this extension to adjust the font size for the user interface:

See also the Gnome display settings in Look and Feel > Appearance > Fonts

Question owner

Thanks!! The Theme and Font Fize Changer add-on is the exact thing to give me the control I needed. There is the same basic add-on for both Firefox and Thunderbird. Also allows you to tweek the background color and other things to make the contrasts and viewablity right for your own needs.

Question owner

Thanks for the reference. Works a bit different in Mint-Cinnamon, but useful to a point. This doesn't address the exact problem I was having, though. The Mozilla add-ons for firefox and thunderbird did the trick for those exact programs.