Hello Emanuele Artusi. I usually use Discord in the app but sometimes I use an account in Edge. I've used that account in Edge many times before and haven't seen that strange folder until now. I have Malwarebytes Premium(Trial Version) working and Windows Defender too and nothing was detected.
Note: The product which I set before is not relevant to this problem anymore as I realised the right one and set it to it, sorry if I made any problems from it.