Hmm, I wonder what "enhanceprotocol''.''co''.''in" is? Well, I think there are three possible sources: (1) One of your open tabs is pushing notifications from that site (2) A tab you already closed left an active background process pushing notifications from that site (3) One of your add-ons is pushing notifications from that site First, you could revoke any notification permission given to that site. There's a box for this on the Settings page. Please check the following article for more information: [[Web Push notifications in Firefox]] (the "How do I revoke Web Push permissions for a specific site?" section). Second, close any tabs with questionable connections. Third, open the Service Workers list by typing or pasting '''about:serviceworkers''' in the address bar and pressing Enter. This page lists scripts that pages have registered to run in the background for push notifications or other kinds of updates. You can unregister any that you don't care about. Finally, if the problem continues, check your add-ons. You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either: * Ctrl+Shift+a (Mac: Command+Shift+a) * "3-bar" menu button (or Tools menu) > Add-ons * type or paste '''about:addons''' in the address bar and press Enter/Return In the left column of the Add-ons page, click Extensions. On the right side, find the "Manage Your Extensions" heading. ''If there is at least one extension before the next heading -- "Recommended Extensions" -- please continue:'' Then cast a critical eye over the list below that heading. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything suspicious or that you just do not remember installing or why? If in doubt, disable (or remove). For your privacy and security, don't let mystery programs linger here. Any improvement?