Really Simple SSL Pro 6.2.5

Extensive scan which enables you to detect the source of mixed content that couldn’t be fixed automatically, with fix button​

Premium email support (details)​

HttpOnly and secure flags to make the cookies more secure​

Improve security by enabling HTTP Strict Transport Security for your site​

Submit your site to the HSTS preload list​

Warning by email and in your SSL dashboard when your certificate is about to expire​

Mixed content fixer for the back-end​

Easy implementable security headers: X-Content-Type-Options, X-XSS-Protection, X-Frame-Options, Expect-CT, Certificate Transparency, No Referrer When Downgrade header, Content Security Policy. Read the security headers article for more info.​