Streaks, smeared lines or blurry web pages while scrolling on Firefox

There is a known issue in Firefox version 49 that causes images and text to display as smeared or streaky lines or tears while scrolling when used with certain older graphics cards. We are working hard to fix this in version 49 with a background update, but in the meantime, follow these steps to resolve the problem:

1. Type in about:config in your address bar.
2. Look for the preference named layers.allow-d3d9-fallback.
3. Double-click this preference and change its value to false.
4. Restart Firefox once for the setting to take effect.