June 01, 2012, 12:06 PM — Here's how you can force web pages to use the fonts and font sizes you prefer in Firefox.
1. Go to Preferences in Firefox.
2. Click the Content tab.
3. Under Fonts & Colors, click the Advanced button.
4. Uncheck the "Allow pages to choose their own fonts..." option.
Now, your default fonts and font sizes will be used when Firefox loads a web page.



















