below r steps && code for quickly leaving all the groups u're a part of
go to ur group membership page && scroll all the way down the page so that all ur groups load
b4 moving fwd i manually left the groups i admin, then when only the groups u're a part of r left copy+paste the code below into ur console ( && press enter )
this will automatically click the "edit" button on each group for u which opens up the submenu. u won't see the submenus ( cause they're hidden ), but when the console says "undefined" then u'll know they're there.
after that, copy+paste the code below ( then click enter ), this will open up all the "Leave Group" boxes ( they'll be one ontop of the other, so it may look like only one is open )
when the "Leave Group" boxes have finished loading copy+paste the code below ( && hit enter ) to automatically leave all ur groups
then refresh ur page