Generally speaking, most sites either use Flash or they use Silverlight, so there shouldn't be any conflict in having both of those installed.

Could you describe the problem in more detail: is the page is just sitting there and it's flashing? Or does it flashes while you are trying to scroll the page, or when it is loading?

Does this happen on all sites, or are there particular sites where you have this problem? Example addresses could be helpful.

Sometimes if the display gets flaky and behaves erratically, it indicates that Firefox is not fully compatible with your graphics card drivers. This can occur after a Windows update or other system update. The standard workaround is to disable Firefox from using hardware acceleration for graphics. Here is where you set that:

"3-bar" menu button (or Tools menu) > Options > Advanced

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

This will take effect the next time you exit and start Firefox up again.

Sometimes the page just sits there when it flashes, but most of the time it flashes on the facebook game when I am scrolling, it will flick and remain on the same page I am trying to scroll away from, when I click a request from friends or trying to visit neighbors, etc.

When you try to click away, I wonder whether that is opening in a new window and an aggressive popup blocker is thwarting it. Usually if Firefox blocks a popup windows, a bar slides down below the toolbar area with some options. However, there could be cases in which that does not appear. To test this theory, you could temporarily turn off pop-up blocking in the Options dialog.

"3-bar" menu button (or Tools menu) > Options > Content

Here you can uncheck the first box and OK the change.

Some security toolbars also block pop-ups. You can review, disable, and often configure/remove extensions on the Add-ons page. Either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions. Then consider whether each extension is useful and, if not disable it. If it is useful and might possibly affect popups or Facebook, try its Options button (if any) to see whether its behavior can be adjusted.