Bookmarking is one the most common method to track the most commonly used pages we use everyday on internet. Pin Tabs takes you one step ahead and allows you to Pin the tabs on top left section of Tabs and you can forget about bookmarking.
You can also configure to keep the tabs always open to safeguard from accidental close and select a shortcut to pin any current open tab.This is an Inbuilt feature of Chrome I was expecting to get into Firefox Core. Download this Firefox Addon from here. Via Ghacks