Hi Portokalia, someone else just posted a similar-sounding issue: [https://support.mozilla.org/questions/1246584 When I click on Youtube, this American Patriot page comes up, and tries to load, but it just keeps cycling, never finish loading.] Both of you shared your extension lists, and both of you have "YouTube High Definition". Could you try disabling it to see whether that makes any difference? 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. Then cast a critical eye over the list on the right side. 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. In addition to that specific extension, you may want to disable anything you do not remember installing or why. Any improvement the next time you go to YouTube (test in a new tab)?