What version of Go are you using (go version)?

$ go version
1.21

Does this issue reproduce with the latest release?

yes

What operating system and processor architecture are you using (go env)?

$ go env

What did you do?

package main

import (
	"fmt"
	"path/filepath"
)

func main() {
	p1 := "/"
	p2 := "../.."

	fmt.Println(filepath.Join(p1, p2))
}

What did you expect to see?

/../..

What did you see instead?

/

I was just wondering if this is the expected behavior.
Just a heads up, Python default path library gives /../..