Firefox is no longer updated on such older OSes, and besides the client application you're using may be abandonware - after all, not only browsers use TLS but a

Firefox is no longer updated on such older OSes, and besides the client application you're using may be abandonware - after all, not only browsers use TLS but also email clients and so on. The only option is to retrofit a newer TLS engine onto a proprietary OS (ha ha), or strip the encryption entirely via a trusted MITM to allow the application to connect at all. > I do personally think it's fairly reasonable for server admins to maintain webservers that target "General-purpose browsing" without also having to include support for odd individual long-tail edge-cases That's a good point