WASHINGTON -- Watching all of those ALS Ice Bucket Challenge videos could come back to haunt Facebook users -- at least financially.
Many Facebook users are receiving surprisingly large bills and notices of high data usage because of the social network's autoplay video function.
Reportedly, more than 2 million ice bucket-related videos have been posted on Facebook, and 28 million people have uploaded, commented or "liked" challenge videos.
That's a lot of data-digesting video playing on a user's mobile device.
According to the consumer site MoneySavingExpert.com, Facebook confirms that videos uploaded to the site will automatically play by default on Wi-Fi, 3G and 4G Internet connections unless a user actively opts out of the function.
Facebook began experimenting with autoplay videos one year ago.
"It's worrying that Facebook is autoplaying videos by default, as it's clearly catching users out, with some claiming they've unknowingly exceeded their data limit and incurrred extra charges as a result," says MoneySavingExpert.com editor Steve Nowottny.
Some Facebook users have received emailed notices from their provider warning that they were approaching monthly data limits, while others didn't realize it until they received bills with unexpected data charges.
How to turn off 'autoplay' on Facebook videos
Thankfully, it's very easy to disable the autoplay function.
Apple: Go to phone's Settings > Click Facebook > Click Settings > In Auto-Play, choose "Wi-Fi only" or "Off."
Android: Go to Facebook app on phone > Click App Settings > Within General Settings, select "Auto-play only on Wi-Fi" or "Off," according to MoneySavingExpert.com.
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