To change the default font size in firefox
1.Go to Tools->Options.
2.Then click Content tab.
3.Then click on Advanced button next to Fonts & Colors.
4.Now select the font,size and minimum font size.
To change the default font size in firefox
1.Go to Tools->Options.
2.Then click Content tab.
3.Then click on Advanced button next to Fonts & Colors.
4.Now select the font,size and minimum font size.