Firefox 47 on Ubuntu render everything too damn big

On my quest to have Emacs bindings on my browser, and after noticing that is there a good extension available to Firefox, I chose switch from Chrome.

Unfortunately, upon opening the Firefox, very big texts, icons, toolbar were shown.

After some googling, I found out that just typing about:config in url bar, accessing the inner config of the browser, then set layout.css.devPixelsPerPx from -1 to 1.3 does the trick.

Nice! Now back to installing Firemacs extension...