Facebook has taken its most aggressive steps yet to counter Snapchat's popularity among teens.
Over the last year the company has duplicated a number of features that Snapchat made famous, including Instagram Stories, which lets users compile multiple annotated photos into a narrative story that disappears, and a very similar basic camera interface.
But this morning, Facebook unveiled three new features that essentially finish the job:
Facebook Camera Effects = Snapchat Filters: According to a blog post, Facebook is rolling out "dozens" of special effects, like "masks, frames, and interactive filters" that users can add to their photos. It will also begin to add branded filters from movies geared toward kids and teens like "Despicable Me 3" and "Guardians of the Galaxy Vol. 2" These kinds of silly and light-hearted filters are core to the Snapchat experience, and a big reason why teens use it to communicate.
Facebook Direct = Snapchat Snaps: A new feature called Facebook Direct will let users share disappearing photos and videos with friends. Recipients can view the photo or video once and respond, then the original disappears forever. This is the functionality that originally made Snapchat popular (and led to the widespread assumption in its early days that it was intended for sending explicit photos).
Facebook Stories = Snapchat Stories: Facebook already added Stories -- collections of photos and videos that are set to disappear after 24 hours -- to Instagram last August. Now, the same functionality is coming to the main Facebook feed.
Snapchat's user growth had already started to slow in the fourth quarter of 2016, according to its IPO filing, and some analysts believe Instagram Stories was the reason.
Now with these three features available to Facebook's nearly 2 billion users, Snapchat will have a harder time staying ahead of the social media giant, especially as it seeks to expand into new countries where Facebook is already popular.
Shares of Snap closed the day down nearly 7 percent.
--Reporting by Julia Boorstin
(Disclosure: CNBC parent NBCUniversal is an investor in Snap.)