Mozilla / Firefox minimization Bug / Feature

Mozilla, Firefox when minimized and opened after a 20/30 mins take a huge CPU suddendly becuase they start to use the memory which they had given up.
To bring back all the tabs and paint the pages, they use this memory,
To stop this from happening...
In the address bar about:config
then
add a new boolean key by right clicking on the list
add the new key as
config.trim_on_minimize and set it to false
Now you can check that Mozilla / Firefox does not give away the memory on minimizing by opening Task Manager and then minimising Mozilla