The star said she was watching a Shane Dawson conspiracy theory video about that and said the following: "I mean think about it, like think about it okay. Guys, I don't even know. I think I am a – what do they call it? Um. A flat – I think they call it a flat-earther."
The video continued to get hilarious as the actress adorably seemed concerned that the person who asked the flat earth question wasn't tuned into the live stream anymore.
Then, she didn't remember who created the conspiracy video she viewed and said Shane Dawson's name many times.
But, the golden comedy moment occurred when she said she's a flat earther but can't remember if that's the right phrase.
After that revelation, Brown said, "Anyway, yeah," before singing Drake's "In My Feelings."
Although the video was posted four years ago, it is still popular online, and fans can't help but reference it, especially the Drake music.
One person on Twitter wrote: "Current mood is still millie bobby brown talking about flat earth and then cutting herself off to sing a drake song."
"Every time I'm in a bad mood, I just remember when Millie Bobby Brown was on [an] Instagram live and said she was a flat earth believer then proceeded to rap 'In My Feelings' by Drake," another added.
A third wrote: "Yea, search Millie Bobby Brown flat Earth on YoutTube. It's one of the funniest videos ever."
Last month, season 4 of Stranger Things was released on Netflix, in which Brown plays Eleven, who has grown up.
She is also reemerging her role as Enola Holmes in the Sherlock Holmes sequel, which should be released in November.
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