Every time you click on a checkbox the permalink is change according to the permission, so its easier to copy the permalink. Therefore when you click the back button you're going to the previous state.
Do you think its not a good behavior?
edit: Actually it doesn't uncheck, it just changes the permalink as if I unchecked. Definitely not the expected behavior. (this is on FF31 Linux)
I fixed it - and now its work with replaceState.
It's won't update until you load it without cache: ctrl+shift+R
Every time you click on a checkbox the permalink is change according to the permission, so its easier to copy the permalink. Therefore when you click the back button you're going to the previous state.
Do you think its not a good behavior?