I installed the new firefox 22 and suddenly everything in or on the browser was bigger and more crowded looking.
So being me, I did a search…
search string : firefox 22 everything is bigger
which found these tips :
which explains this :
hello, firefox 22 is now respecting the pixel density you’ve set on a system level in the windows control panel > appearance > display. more information about that is availbale at http://windows.microsoft.com/en-us/windows7/make-the-text-on-your-screen-larger-or-smaller
if you want to set the text size/pixel density in firefox different from that of your system’s settings like it was handled in prior versions, enter about:config into the firefox address bar (confirm the info message in case it shows up) & search for the preference named layout.css.devPixelsPerPx. double-click it and change its value to 1.0 (or any other zoom factor that fits your purpose; -1.0 is the default value and will adhere to the system settings).
The short & sweet Woog version :
in the firefox address bar type: about:config
find this :
modify from -1.0 to 1.0 or 2.0 to preference.
see things change.