Change size of text - Thunderbird Version 3

To change the font size for incoming plain text messages, follow these steps:

Go to Thunderbird > Preferences.

Choose the Preferences option from the Thunderbird Menu
  • Click Display.
  • click Advanced...
Click on Display
  • If Use fixed width font for plain text messages is selected, set the minimum font size to the smallest font  you can comfortably see.
  • Click OK.
If Use fixed width font for plain text messages is selected,