I connected my Fire TV and tried Prime UHD content, but got the message it is lacking HDCP 2.2. So does this mean I must rely on the native built in Prime app? Same thing for netflix? I can't use my Fire TV netflix app, must use the smart tv apps?

My Fire TV is running Kodi 75% of the time, what if I play a 4k file inside kodi, would it play in 4k or downconvert it to 1080p??