Microsoft today announced that they have added support for TCP Fast Open in Microsoft Edge behind an about:flags setting in Windows Insider Preview builds, starting with EdgeHTML 14.14361 and higher. With TCP Fast Open, we can enjoy improved performance.
We know performance and security matter to our users and we’re committed to delivering a 0-RTT experience in Microsoft Edge through HTTP 2.0, TLS 1.3, TCP Fast Open, and TLS False Start. We’re also going to continue to work with industry leaders and experts in the standards bodies to build an interoperable TLS 1.3 solution for the web.
Read about this in detail from the source link below.