Each major Go release is supported until there are two newer major releases. https://golang.org/doc/devel/release.html#policy
Echo CORE tests with last FOUR major releases (unless there are pressing vulnerabilities) As this library depends on MANY DIFFERENT libraries which of SOME support only last 2 Go releases we could have situations when we derive from last four major releases promise.
p.s. you really should use latest versions of Go as there are many vulnerebilites fixed only in supported versions. Please see https://pkg.go.dev/vuln/