Jim Carrey thinks the NFL and Donald Trump are the real "Dumb and Dumber" ... and he's attacking BOTH of 'em for the alleged blackballing of Colin Kaepernick.
"NFL -- who exploits players for 3yrs then abandons them to a lifetime of pain -- sided with a draft-dodging racist who uses fake patriotism to squash peaceful protest," Carrey posted on Twitter.
Carrey then sorta called on companies that do business with the NFL to boycott the league.
"Corporations shld rethink sponsoring moral cowardice before we start asking: whose side is Nationwide really on?