Superman will find his red underwear in Action Comics #1000 - Polygon

And he’ll be wearing it on the outside

A Look Inside Superman Red Trunks in Today's Action Comics #1000 (Semi-SPOILERS)

Superman will find his red underwear in Action Comics #1000 - Polygon

Action Comics celebrates issue #1000 with red trunks

Superman hoping to make red trunks cool again, getting old look back in Action Comics No. 1000

Superman's Red Trunks Return in Action Comics #1000 - IGN

Superman hoping to make red trunks cool again, getting old look back in Action Comics No. 1000

DC comics' Tom King & Brian Bendis: Batman, Superman, and the industry - Polygon

A Look Inside Superman Red Trunks in Today's Action Comics #1000 (Semi-SPOILERS)

Do Superman's red underwear serve any purpose other than being aesthetically pleasing or for comfort reasons? - Quora