That is a TrueKey support to resolve their addon installation issue.

''<p>martier2012 [[#question-1494660|said]]</p>'' <blockquote>I installed Truekey in Firefox. It says it's on in settings/extensions, but the icon in the toolbar says it's off and it's not working. </blockquote> Hi, did you install from https://www.truekey.com/ -- I did that, and the first thing that happened was a new tab opened saying: <blockquote>You're not protected Turn on personal data collection so we can help keep you safe from threats while browsing the web. Otherwise, you'll need to uninstall McAfee® True Key.</blockquote> That's annoying. So I approved that. Now the toolbar button has OFF at the bottom. When I click that button, a new tab opens with a moz-extension:// address showing a sign-in page where I would need to create a new profile to continue. Are you getting this page? I stopped there since I'm not looking to create an account.