4 original tabs open in firefox but 12 in pc task manager

I have many more tabs open in the background then I actually have. I am not good at this but I can give what I know I am experiencing. 1st photo has16 tabs open in pc's task manager 2nd photo shows that I only had 2 tabs open in Firefox browser 3rd picture show 19 in task manager. I expanded in task manager the Firefox app and right clicked to end task to remove what might be ghosts tabs running in task manager. ----That did not work There are currently 6 of them that has the efficiency mode on the 19 tabs.

Firefox is getting complicating for my abilities but I appreciate using Firefox for all the flexibility. I usually ask a friend to set me up or help but he is unavailable and this seems to be above his head to. Crossing my fingers for a easy solution. Thank you, Happycamper