I am out of ideas.
I can cast to my chromecast from the Emby mobile app, either from ipad or iphone.
On PC and Mac, in Google Chrome (updated and it is not a dev version) the chromecast doesn't show up in the list of devices.
On the same PC or Mac, I can cast to my chromecast from youtube or any castable website. In the Chrome's menu I can cast to my chromecast, but notbfrom within Emby web app.
I am not using a VPN. My server is not located on the local network, I access it through internet usual port.
Suggestions much welcome as I am new in the Chromecast world.