There are several instances in '90s sitcoms where art gets messed up, but the one you're probably remembering might be from The Fresh Prince of Bel-Air. There's an episode where Will and Carlton are at an auction, inadvertently vandalize a portrait by spraying water on it. They then buy it to hide the mishap. The episode is called 'I, Stank Hole in One' from Season 5 if you want to check it out. Quite iconic and usually makes it to compilation videos.

Are you sure you're not confusing it with a movie? I can't recall a 90s sitcom where a painting gets ruined. Unless we're stretching it and considering 'Boy Meets World' where Cory touched up a painting but that's not a mess-up, just an art class scene.

You're definitely thinking of Full House! There’s an episode where DJ and Stephanie accidentally punch a hole in Danny’s wall and then cover it up with a Jesse and the Rippers poster. It’s not exactly a painting but it was a huge mess up LOL. Check Season 3, Episode 3, 'The First Day of School' 💥

Maybe it's a ghost episode and the painting messed itself up? :P

idk if this helps but there was an ep of 'Everybody Loves Raymond' where Ray's dad backs into a table and breaks this big important wedding gift vase. It's not a painting but maybe you're mixing up the eps?

hmm yea I don't think that happens in Friends? or seinfeld tbh... maybe try looking up shows like 'Married with Children' or 'The Fresh Prince', could be in those too. those kind of physical comedy gags were everywhere back then lol.

Oh, I totally know what you're talking about! There's an episode of Friends called 'The One With the Fake Monica' (Season 1, Episode 21). In that one, Ross buys a super ugly painting from Monica's fake friend's art show. It doesn't get messed up per se, but it's used as a gag for a bad painting. That might not be it, but it sprung to mind!