Hi   ! Don't know if this will do the trick, but maybe you'd like to try this add-on : https://addons.mozilla.org/en-us/firefox/addon/anti-aliasing-tuner/ ClearType Level : The degree to which the red, green, and blue subpixels of each pixel are treated differently. Valid value range is from 0% (meaning no ClearType, which is equivalent to greyscale) to 100% (meaning full ClearType). Default is 50% typically, but depends on your environment.