Android Navigation overflow menu item overlapping fargments

I have been learning android navigation components from codelab, after following through steps, at step 8 I came across to a weird bug.

Steps to reproduce:

1. Enter application.
2. From the overflow menu select Settings option. SettingsFragment is added and overflow menu is visible.
3. Again, select the Settings option from the overflow menu.
4. Press back.

see following screenshots mainfragment settings Fragmentafter clicking settings fragment again

This is an issue issued in google issue tracker which was an internal bug for navigation aac, to fix add navigationVersion = "1.0.0-alpha02" in your build.gradle file