UPDATE: I deleted my earlier post because after being up for several hours, the FireTV Cube started working with Alexa smart home camera skills including Monocle. I received the Amazon FireTV Cube today (2018-06-21) and at first it was not working with Alexa smart home camera skills. However, after leaving it up for a number of hours and re-testing its now working with the Monocle camera skill to show my IP camera feeds. NOTE: However just like the FireTV 4K (3rd Gen), the FireTV Cube does require using the new Monocle Gateway service which is currently in BETA testing. See: https://forum.monoclecam.com/category/5/beta

Command line installation into /opt/monocle after “su -” went exactly per instructions on Fedora 31 Linux. Yi Home 1080P with yi-hack ONVIF/rtsp firmware and Amcrest R2c with stock firmware work perfectly on Alexa with @proxy tag.

Fantastic! Downloaded the token no problem. Thanks!!