Browser Navigation Tracker

I some time found it difficult to get back to the original post from where i started clicking hyper links.
I get deep down to my sub topic so deeply that i forgot where did i started this.
Lets illustrate it through a figure.




Here if start from topic A and reached to Topic A21 there there is no way by which 1 can immediately get back to either parent topic A2 or parent of parent topic i.e Topic A.
Now what i suggest there should be a "Back To Parent" button in Browser by which i can move immediately to parent tab.
Browser can have a setting for that like enable parent tracking...