Internet Explorer doesn't support SNI on Windows XP, correct. Let's Encrypt doesn't force you to use SNI, though. SNI is not something you "stick" on a certifi

Internet Explorer doesn't support SNI on Windows XP, correct. Let's Encrypt doesn't force you to use SNI, though. SNI is not something you "stick" on a certificate - it's a TLS extension which you don't have to use at all.