The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

1. Go to Firefox > Help > Troubleshooting Information.
2. Click the "Reset Firefox" button.
3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
4. Firefox will open with all factory defaults applied.

Further information can be found in the Refresh Firefox - reset add-ons and settings article.

Did this fix your problems? Please report back to us!

No, that didn't fix it. In the middle of typing this reply, the cursor will disappear and nothing I type shows up. I have to left click to get it back so I can continue typing. Page down or up will work once, maybe twice but then stops. So no change.

Hello Gnail, check it in Safe Mode, in Safe Mode window select "Start in Safe Mode" and see if this happen again, if not then see: Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

(If the problem does not happen in Safe Mode, it is most likely because of an extension and you need to figure out which one, or maybe hardware acceleration).

To exit the Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

also : can you check in a new profile ?

thank you

I'm answering in Safe Mode now and having the same issues - page up and down only working intermittently - cursor disappearing while typing and have to left click to get it back so can continue typing this. I did go back and try IE and it is happening there as well.

try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) and check it again (If works in Windows Safe mode then you have a problem with other software, like security software[antivirus, firewall] or a system driver, that is running on your computer).

see also : Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

You can try these free programs to scan for malware, which work with your existing antivirus software:

• Microsoft Safety Scanner
• MalwareBytes' Anti-Malware
• TDSSKiller - AntiRootkit Utility

Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one.

Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Did this fix your problems? Please report back to us!

Try to disable hardware acceleration in Firefox.

• Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available"
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

• https://hacks.mozilla.org/2010/09/hardware-acceleration/

If there is a problem with scrolling on web pages then try to disable smooth scrolling.

• Tools > Options > Advanced > General: Browsing: "Use smooth scrolling"

Booted laptop in Safe Mode and had no issues - worked as it should. Disabled hardware acceleration and smooth scrolling which had no impact - same problems. So this points to security software or a driver?

If it works in Windows Safe mode then you have a problem with other software, likely security software or a system driver, that is running on your computer.
Make sure that you have the latest updates of your security software and major hardware drivers like the graphic display driver.

You can use the MSConfig program or the Autoruns utility to see which software and services are getting started.

• http://technet.microsoft.com/en-us/sysinternals/bb963902.aspx