Hello, Is there an example webpage where this is happening. Sometime there are pieces of a webpage that take longer to load than others.

Mozilla is working on e10s a window mode that accelerates loading.

However in the meantime let's troubleshoot the smooth scrolling. It is possible to toggle the preference in : about:preferences#advanced in a url bar and under Browsing there is an option to uncheck smooth scrolling.

It is also possible to check to see if it is affected by the site trying to use hardware acceleration: Diagnose Firefox issues using Troubleshoot Mode

Also check to make sure your mouse driver is up to date if it is also happening in other applications.

As I said above, I've already tried everything you suggest. How could it be any of those anyway when everything (mouse and all) work fine with the other browsers.

However after updating and installing separately the latest version of Java for Firefox, seems like the issue is resolved!

I still can't be sure though as I need some more time.

Keeping you informed!

Thanks for your support anyway!

Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

• http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/

I've done that before the installation of Java and it didn't help!

Now, after updating Java the issue hasn't appeared yet!

Cross my fingers and keeping you informed!

By the way do you believe that the outdated version of Java on Firefox before, had nothing to do with this issue?

It is possible it seems that is does.