A friend had a gen-1 Chromecast in-box new that they had never used and they gave it to me rather than throw it out.
I would like to stream to it from my N900.

Several questions... (mostly answered in post)

1- is this inviting the corporate cyberpunk NSA/KGB into my home?(YES!) does it force it own network 'calls' home to my enemy Google?(YES!)

2- If this is a network spy, can I neuter this gadget?(YES!!) Maybe a custom user respecting firmware?(see below)

3- if I can neuter this gadget is there a way to do setup with a linux computer or un-googled LineageOS(microG) tablet without ever involving google?(yes, need Teensy AVR dev board, a USB flash drive, and powered OTG cable)

4- If a no-Google setup is possible(it is) is there a way to stream from a Maemo device? What protocol is in use? Is it possible to just hack a crappy python script together or VPN over with the libs we have on our phones already?

To answer most of above, I plan on reflashing with Eureka(need a powered microUSB OTG cable, I can also use it with my N900 and tablet) so I can own this hardware rather than google pwning me and my network.
**Until I can make or buy and deliver a powered OTG cable I am still wondering about a N900 video/audio stream.**
Answers:
If you ever find a new Chromecast DO NOT ever connect or register as the updates may make it unrootable.
How To: Rooting and flashing Eureka firmware(seems mostly or all FOSS GPL v2 or 3 not sure about bin blobs or libs)
https://team-eureka.com/
https://github.com/team-eureka

https://forum.xda-developers.com/sho....php?t=2578653
https://forum.xda-developers.com/sho....php?t=2452838
apparently all tech documentation now has to be on Youtube too so...
https://www.youtube.com/watch?v=A7BedB1AQls