Fetching details from the dictionary...
going up in flames; destruction by fire (esp. of a large building)
stirring up a storm of criticism online (of an article, tweet, statement, etc.); becoming the target of an Internet pitchfork mob
有名人のSNSが炎上中だ。
A celebrity's SNS is getting flamed.
その発言がネットで炎上した。
That statement caused online backlash.
炎上を避けるために注意する。
I'm careful to avoid online flames.