If you have increased the minimum font size then try the default setting "none" as a (too) high value can cause issues. *Tools > Options > Content : Fonts & Colors > Advanced > Minimum Font Size (none) Make sure that you allow websites to choose their fonts. *Tools > Options > Content : Fonts & Colors > Advanced > [X] "Allow pages to choose their own fonts, instead of my selections above" *https://support.mozilla.org/kb/Changing+fonts+and+colors It is better not to increase the minimum font size, but use an extension to set the default page zoom to prevent issues with overlapping text. *Default FullZoom Level: https://addons.mozilla.org/firefox/addon/default-fullzoom-level/ *NoSquint: https://addons.mozilla.org/firefox/addon/nosquint/

Thanks, I'll give it a try and report back!