As part of a safety update, Meta is implementing a change that will default to turning off the option for individuals under 18 to receive messages on Instagram and Messenger from users they do not follow or have no connection with.
The social media giant said the change is part of its ongoing work to provide "age-appropriate experiences for teens" across its apps.
The change extends an existing meta policy that does not allow adults to message teenagers who do not follow them, meaning no one on Instagram or Facebook Messenger will be able to message a teenager who does not follow them directly.
"Under this new default setting, teens can only be messaged or added to group chats by people they already follow or are connected to, helping teens and their parents feel even more confident that they won't hear from people they don't know in their DMs," Meta said in a blog post.
"This default setting will apply to all teens under 16 (or under 18 in certain countries). Those already on Instagram will see a notification at the top of their feed letting them know we're making these changes to their message settings," Meta said.
"We're also making these changes to teens' default settings on Messenger, where under-16s (or under 18 in certain countries) will only receive messages from Facebook friends or people they're connected to through phone contacts, for example."
In a further safety update, Meta said parents using its existing supervision tools will now have the ability to approve or deny their teenagers' requests to change their default privacy and safety settings.
Until now, parents have just been notified when their child changed.
"For example, if a teen using supervision tries to change their account from private to public, change their sensitive content control from 'less' to 'standard,' or – now – tries to change their DM settings to hear from people they're not already following or connected to, their parent will receive a notification prompting them to approve or deny the request," Meta said.
The update comes as social media platforms continue to face scrutiny over their impact on younger users.