In the live, Millie was answering questions for fans when James' comment appeared.
"Millie let's film a makeup video & talk abt season 3 hehe," he wrote.
Right as his comment popped up, Millie made a bizarre face that bordered on disgust and appeared to lose her train of thought momentarily.
However, she quickly regained her composure — acting like she was going to try to do an accent but had changed her mind.
Of course, fans were living for the drama, taking to Twitter to analyse Millie's reaction.
It comes as a bit of a surprise, as the pair seem to have been good mates in the past.
Millie even appeared in James' video where he revealed private DMs from his celeb friends, where she dished out beauty advice and words of encouragement.
But even that hasn't convinced fans that James and Millie are cool, with some noting that her responses seem 'short.'
Was it just a common misunderstanding, or has Millie taken Tati Westbook's side in her feud with James? Hey, stranger things have happened!
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