Since you are familiar with how these sites work, can you describe where it is breaking down? For example, does the coupon usually open in a separate tab or a separate pop-up window, and that is no longer opening? Or if it opens, does it stay blank? The more information you can provide along these lines, the better. To see whether one of your extensions could be the culprit, could you try printing the coupons in Firefox's Safe Mode? That's a standard diagnostic tool to bypass interference by extensions (and some custom settings). More info: [[Troubleshoot Firefox issues using Safe Mode]]. You can restart Firefox in Safe Mode using Help > Restart with Add-ons Disabled In the dialog, click "Start in Safe Mode" (''not'' Reset) Any difference?