Installed Test Pilot Experiments and when I got to the Tabs Center, now Firefox is all gray and the bottom bar is halfway cut off no matter what size I make the window. I tried several of my bookmarks and nothing is displayed, all gray. Even the options and add-on pages are all gray. BTW... I can't add an image from the button below (maybe because I am using Chrome? Icon just spins forever). OK, I found the 'Restart Firefox w/ Add-ons Disabled' in the Help menu. Did that and removed the Test Pilot, no change. It is gone but still just a gray screen in Firefox. I am trying to reload the Test Pilot and disable the Tabs Experiment but it has been saying installing for over 10 minutes now and nothing else is happening (no pop-up or such install is going on). Luckily I have Chrome installed so I can post this.