WildFly users get the new Undertow out of the box, standalone users can just get the latest Undertow via maven as detailed here:
I want to thank Masafumi Miura, who wrote the SameSiteCookieHandler added to Undertow, and all contributors from the community, who actively
participated in the project and submitted several bug fixes to Undertow in the past release cycle.
A special thanks goes to Carter Kozak, who contributed a great deal of HTTP2 fixes in the latest releases of Undertow (most of those fixes were included in Undertow 2.0.30.Final; all merged fixes are available in 2.1.0.Final)
Stay tuned for news on future Undertow releases!
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