A headless pikaraoke server can be accessed on a Chromecast a couple of ways:

First, start a pikaraoke server with the --headless option. Make a note of the splash screen URL.

• On computer that is connected to the same wifi, open Chrome browser
• Open the splash screen URL (ex: http://192.168.86.34:5555/splash )
• Cast this tab to your chromecast (cast is under the triple dot menu > Cast, save, and share > Cast )

• On another computer on the same wifi, visit: URL Cast Receiver - https://demille.github.io/url-cast-receiver/ (this is a utility for sending a URL to your chromecast to open it in its native browser)
• Click "start cast session" and select your chromecast
• Select "location" from the dropdown (not "iframe")
• Enter the splash screen URL, but add ?confirm=false to the end of it to hide the interaction confirmation prompt (ex: http://192.168.86.34:5555/splash?confirm=false )
• Click "send" to tell the chromecast to open this URL in the browser