5 minutes, not 4.As @Cynamooo said, you upload it to YouTube, I recommend putting it as unlisted but make sure you do not make the video private because then only you will be able to view it and the hacker will not get banned. Also make sure it is under 4 minutes of evidence. If it does not work after that then the last thing I know of is to wait a bit and then try again, the video might not have processed yet.
Any video format is supported..mp4
Indeed, this will!You need to upload the video to YouTube and than copy the link and put it in your report.