Hello Sam Wold Here is the link to Unity 4.3.0 release notes, & in the release notes it explains which TLS is supported.  [URL]   TLS is supported in later FW release levels as well. Please let us know if you have any other questions.
Does Unity 4.3.0.xx FW level support TLS 1.2 level?  If Unity is upgraded to 5.x or 6.x FW levels, will TLS 1.2 be automatically supported?
Does Unity 4.3.0.xx FW level support TLS 1.2 level?