Mozilla Firefox Help

  Firefox blocks Secure Sockets Layer version 3.0 (SSLv3) to protect your information from attacks. SSLv3 is a type of technology that some websites use to connect to a server. It is no longer secure, which makes it easy for hackers to extract your personal information during a connection. For more information, see  Fix Firefox Error What happens when you access vulnerable sites When you try to access a site that only supports Secure Sockets Layer version 3.0 (SSLv3), Firefox blocks it and displays a message,   Unable to Connect Securely , explaining that Firefox cannot guarantee the safety of your data on that website because it uses SSLv3, a broken security protocol. If you see this message, please contact the website owner to let them know about the problem. Additional precautions To further protect yourself from attacks, keep Firefox up to date. The simplest way to do this is to set up automatic updates: Click the menu button   and select  Options ...

  A  user agent  tells websites what type of browser and operating system you're using. This information helps the web server deliver content that's compatible with your browser. If websites tell you that your browser is outdated or incompatible even though Firefox is up to date, an incorrect user agent may be the cause. This article explains how to fix problems with your Firefox user agent so that websites work properly.  Fix Firefox Error User agent issues You can change Firefox's user agent to trick websites into thinking that you're using a different browser or operating system. Web developers might do this to see how their websites will appear on different systems and browsers. Sometimes, add-ons and other installations can change your user agent without your knowledge. Websites may not display correctly or may show a message that your browser is outdated or incompatible, based on the detected user agent. It's important to switch Firefox back to the  defaul...