I wrote this little snippet to account for Firefox 22+ scaling sites larger on Windows to honor window DPI scaling settings. Requires the browser plugin found here... http://jquery.thewikies.com/browser/

jQuery: Firefox Scaling Fix

var windows = (navigator.platform.toLowerCase() == 'win16' || navigator.platform.toLowerCase() == 'win32') ? true : false;
	console.log(windows);
	if($.browser.name == 'firefox' && $.browser.versionNumber >= 22 && windows == true){
		$('html').css('-moz-transform', 'scale(0.8)');
	}