Thanks. I reinstalled the app, cleared data and cache, but it was still unable to stream any content. Then I noticed the chromecast was acting weird, it was lagging, it was getting very, very slow connection speed, like if it was applying updates or running maintenance, I don’t know for sure. I checked again next day, and now is is working as expected.

If not for the fact that I really like the form factor of this device, I would ditch it.

Otoh, the logs are in the post, maybe your client is not rendering > markdown < properly.

I think that would be something related to your DE. In my case, I have the Plasma Integration plugin in both Firefox and Chromium-based browsers, allowing me to play videos full screen for long periods, the only nag being that if I have it full screen on one of my displays but there is any other window focused, it triggers the screensaver. For those cases, there are a few ways on KDE to prevent the displays to enter any saving mode with no more than 2 clicks, or a shortcut if you prefer to configure those

https://sonoff.tech/product/diy-smart-switches/zbmini/

I have installed LEDLUX smart wall socket (around 25€), MOES light switches (around 30€ for a 2-gang switch), both of which are quite easy to install as it replaces what you already have. I have used Sonoff zigbee relays (around 50€ for a pack of 4) as well as Avatto mini zigbee smart switch modules (around 20€, single and 4-gang modules), but it may require some modifications on your current installation

Or go with a zero, plug and play socket, like the Nous A1Z smart socket, around 15€ each. Just plug it onto your wall socket.