However, she noted that this feature seems to be in an "early stage of development" -- it's only appearing on the app's Groups tab with some dark text displaying against a dark background, making it tough to read. So it might be a while before Facebook's mobile dark mode gets a wide rollout.
The company didn't immediately respond to a request for comment.
Last week, Facebook's Messenger Kids, a version of the messaging app designed for 6- to 12-year-olds, came under scrutiny from US lawmakers after a flaw let children chat with people who hadn't been approved by their parents.
First published at 3:01 a.m. PT. Updated at 3:20 a.m. PT: Adds more detail.
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