If you haven't already, try disabling Firefox's use of hardware acceleration for graphics. This is a common workaround for incompatibilities with graphic card drivers after an upgrade, rollback, or other change.

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

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

This will take effect after you exit and restart Firefox.

If the problem continues, try disabling another related feature. This requires a visit to the about:config preferences editor.

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(2) In the search box above the list, type or paste gfx and pause while the list is filtered

(3) Double-click the gfx.content.azure.enabled preference to switch its value from true to false.

I can't recall whether this takes effect immediately or after a restart.

Any luck?

If you would like to post a screen shot, you can attach it to a reply in this thread. There's a Browse button below the text box.

jscher2000

Thanks for your great help, my Firefox resumes normal.

Cheers!

Steve