Block Whatsapp web data upload and download

Hi all,

what I'm trying to do is to allow Whatsapp web for my users, but only as chat service. I want to block possibility to upload and download any kind of files, to be compliant with our DLP policy.

I think I can create a web policy to do it, rather than using control application, but I didn't find how proceed.

Do you have any suggestions or ideas?

Thanks for your help.

Kind Regads,