The 28-year-old rapper angered fans Monday by leaving an emoji on a photo of Rihanna's outfit for the traditional festival in Barbados.
Brown posted an emoji of two eyes after Rihanna shared pictures on Instagram of her dazzling ensemble. Thousands of people liked his comment within hours, while others warned the star to stay away.
"PLs keep your negative energy away from Rihanna @ChrisBrownOfficial," one fan wrote.
"Chris Brown just leave her alone my guy," another added on Twitter.
Chris brown just leave her alone my guy pic.twitter.com/PiKvvzAVYf— Young Durant (@A_Geechi) August 8, 2017
Brown pleaded guilty to domestic violence charges in 2009 after beating Rihanna prior to the Grammy Awards. He and the singer later appeared to get back together, but split again in April 2013.
"I was very protective of him. I felt that people didn't understand him. Even after," Rihanna said of Brown in the November 2015 issue of Vanity Fair. "But you know, you realize after a while that in that situation you're the enemy."
"Sometimes you just have to walk away," she added. "I don't hate him. I will care about him until the day I die. We're not friends, but it's not like we're enemies. We don't have much of a relationship now."
Brown said in the documentary Welcome to My Life, which debuted in June, that he felt like a "monster" following the assault. He confessed he considered suicide at the time, saying he "wasn't sleeping" and "barely ate."