Another problem at Starbucks ... but this time it ain't the coffee company's fault, because Lil Uzi Vert chased his enemy Rich the Kid right over the counter.
It started on the streets of Philly -- Uzi's hometown. Rich was in town to perform at the Roots Picnic Festival, where Uzi was slated to perform as well.
Check out the video .. Uzi confronts Rich, who then scampers away. But it doesn't end there. There was a full-on melee at a nearby Starbucks.
The feud was triggered 3 years ago, when Uzi signed with DJ Drama's Imprint. It didn't sit well with Rich, who wanted Uzi to sign with him.
As for the music festival ... Uzi and Rich both performed. In fact, Rich wore the same gear he was wearing during the Starbucks confrontation.