I was looking changes of Configuration Page Redesign (https://github.com/jenkinsci/jenkins/pull/6485) and I have found that if you click on Build-Steps or Post-build Actions, you will be referred to Build Environment, rather than one of those two.

I have tried to click on Post-build Actions, but it referred me to Build Environment, after clicking the mouse, hover on Post-build Actions will disappear, but Build Environment will be hovered/selected (even if we didn’t click on it)