One feature introduced in this version of Firefox is a warning that prompts users when trying to log into a non-secure HTTP (Hyper Text Transfer Protocol) website. To keep users safe online, Mozilla is encouraging users to use HTTPS (Hyper Text Transfer Protocol Secure) for their websites.
If your browser has updated and you've tried visiting a website that doesn't have an SSL (Secure Sockets Layer) certificate installed, then you may have seen a warning like the below when trying to log into the website.
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You can read more about whether you should switch from HTTP to HTTPS in our blog post here.
Ordering an SSL certificate is simple, and is something that your hosting provider should be able to assist with.