Error on logout and after logout click on back has taken to my profile

In Crome browser on first click on logout I got the following error(Image 1), then I clicked back and again clicked on logout , this time I logged out successfully but when I clicked on back I reached to my profile page again(May be because

I was loggedin in another tab , I don't know the reason ).

In safari browser I tried to do the same ,every time I got the 404 error, image 2.

I was not able to move(adjust) the profile pic while uploading so my full face is not there in my profile pic.