Under Admin -> Attachments, set the maximum file size to something that is ok for documents, but useless for video. This won't stop it, but your users won't be able to upload videos of much use.
If that's not going to work for you, then you need add-ons that can scan and refuse attachments - there's a couple in the marketplace, have a look for them.
Hi my Community friends! For those who don't know me, I'm a product marketer on the Confluence Cloud team - nice to meet you! For those of you who do, you know that I've been all up in your Co...
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