Earlier quoted context omitted.
Its been my recent experience too, I keep a lot of tabs open and began to notice Chrome was filling up my memory. Very strange that Google let the situation get so bad. Mind you I find the Chrome developer tools far more powerful and intuitive than those in Firefox which stops me moving entirely.
I hear quite a few people talking how they have 30-50 tabs open, how do people manage something like that? And why would anyone need so many simultaneous tabs open?
So then you devote a couple of hours to going through and closing tabs, and find you still have 300...
The solution, if anyone ever gets this far down the page, is to use Session Manager to save the tabs, close Firefox, and then just uncheck the boxes for the tabs you don't ever want to reload.