Firefox Theme Font Size Changer

Martin Brinkmann
May 29, 2010
Updated • Jun 26, 2013
Firefox, Firefox add-ons

Experienced computer users can tweak many Firefox settings in the configuration files and style files that ship with the browser. Almost everything that is displayed on screen can be changed if the proper commands are known.

Hacking the style files on the other hand is not something that every user can do nor wants to do.The main issue here is that users need to find out about the commands that they can use. While that is often possible by searching on the Internet for what you want to do, you sometimes may come up empty.

That's where add-ons like Theme Font Size Changer comes into play. Add-ons are another - more convenient - way of changing Firefox elements and styles as they can modify parameters and values as well.

This particular add-on changes the font size of the Firefox theme. Firefox theme in this regard means all interface elements that display text including tabs, menus, status bar, address bar and other toolbars and even the context menu of the browser.

The add-on places an icon in the Firefox status bar that will open the font size selection menu when pressed. Selecting a new font size will instantly change the size of all Firefox interface elements to the selected size.

The font size selector offers one entry to reset the font size to the normal one used in Firefox by default. This is helpful in case the changes turn out to make interface elements inaccessible or unreadable.

Theme Font Size Changer can be downloaded from the official Mozilla Firefox add-on repository.

Update: The latest version of the extension for Firefox offers additional preferences that you can modify. When you click on the icon it adds to the main toolbar of the browser, you will notice that a new window is opened displaying the available preferences.

theme font size changer

The following options are available:

  • Font type - Select a different font that you want to be used for all Firefox interface elements.
  • Size - Change the size of all Firefox interface elements.
  • Style - Select to use the normal style or italic style.
  • Weight - Use normal weight or bold weight.
  • Color - Pick a different color for all menus.
  • Background Color - Select a different background color.

Tutorials & Tips

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  1. Shatimi said on May 29, 2010 at 4:15 pm

    Could You tell what Firefox theme do You use? Thanks in advance :)

    1. Martin said on May 29, 2010 at 4:45 pm

      It is the Operetta theme ;)

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