Need to scroll up on a webpage? Let us keep this simple. You need to pick up the Scroll Up add-on for the Firefox browser. It brings a small arrow into the interface that helps you jump back up. It is really that easy.
Here is a little more about the add-on:
Scroll UP to the top of the page. You will see a small arrow at the right bottom corner of the webpage when you scroll down. Clicking on it will take you straight up to the top of the page.
If you want to pick up this add-on, check it out at the Firefox Add-ons website.