Good news, Dropbox users! Facebook Messenger now accepts Dropbox files for sharing directly in the app, without having to copy and paste a thing.
Instead of generating a shareable link and giving it out to users, Messenger now supports direct sharing of Dropbox files. You can add a video, picture, or text document as long as you have both the Messenger and Dropbox applications installed on your phone.
In a message thread, just tap the “More” button and locate the new Dropbox button. Once selected, a list of your Dropbox files will be available for sharing.
If you’re still not seeing the new feature, don’t fret, as Facebook says the feature is rolling out incrementally.
Source: Official post