My biggest peeve is when I am admin working in the devloper suite, the scroll bars at the bottom and the side are tiny. If the browser window is full screen you end up popping up windows taksbar at the bottom everytime you go to scroll becuase it it so thin.
Please enlargen it to a more useable size and dare I say it perhaps allow for them to be a bit bigger on screen apps as well
A (possibly little known?) feature in browsers is you can hold the shift key while scrolling up and down with your scrollwheel in order to scroll side to side. The scrollbars are also already thicker on Chrome and Safari based browsers, but Firefox doesn’t currently support the CSS used for this.
Doesn’t completely solve the problem, but might hopefully help.