That looks like a problem with hardware acceleration.

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

You can use one of these to start Firefox in Safe Mode:

• On Windows, hold down the Shift key while starting Firefox with a double-click on the Firefox desktop shortcut
• On Mac, hold down the Options key while starting Firefox
• Help > Restart with Add-ons Disabled

• https://support.mozilla.org/kb/Safe+Mode

Thanks! Appreciate it! :D

You're welcome

Edit: This is what happens when I get distracted while composing a post. Never mind.

I think Firefox is incompatible with your graphics card drivers. Try the following:

(1) Start Firefox to a blank page

In the Windows 7 Start menu, search box, type or paste the following and then press Enter:

firefox.exe about:blank

(2) Disable Firefox's use of hardware graphics acceleration

orange Firefox button (or Tools menu) > Options > Advanced

On the "General" mini-tab, uncheck the box for "Use hardware acceleration when available"

Then exit and restart Firefox normally.

Any improvement?

Hi, my Firefox is working now. You are correct, I installed new graphic card driver on my hardware. This issue is resolved now, appreciate your help guys!