In the address bar type about:config and press enter.
Accept the risk involved while making changes.
Search for mousewheel.acceleration.start
By default its value should be -1 which indicates the option is disabled. To enable, change its value to 0 by double-clicking on it.
Comparing to Google Chrome, Firefox has very slow scrolling speed for web pages. It is smoother than Chrome but not just fast enough. So I usually go for the scroll bar, which needs little more effort. Move the cursor to grab that scroll stick and drag the mouse up & down.
You know that our universe, which contains our earth, sun, other stars, planets surrounding these stars, our Milky Way galaxy, other galaxies, everything you name it; is expanding. Thanks to Georges Lemaître and Edwin Hubble who figured out about the expansion.
What does it mean? It means, our earth along with its residents, actually floating and moving, within its own galaxy, through the very basic fabric of the universe. Can you imagine? We are not staying still in one position. WE ARE MOVING! Literally through space and time. If you look at the whole picture, everything is moving. And that is how the universe works.