https://www.cnet.com/news/maroon-5-singing-spongebob-at-super-bowl-looking-more-and-more-likely/

On Jan. 30, Jamal N. Williams, anchor at Chattanooga, Tennessee's WDEF-TV, tweeted out a glimpse of Maroon 5 rehearsing for the Super Bowl halftime show at Atlanta's Mercedes-Benz Stadium. 

And what's that on the huge screen? It appears to be SpongeBob himself, likely in a clip from the season 2 episode where he performs at Bikini Bottom's version of the Super Bowl.