I am using the code as is in this repository. The cast button does not show up if I use my application id.
Also more than 50% of the time, there is an error in the console stating

Uncaught ReferenceError: cast is not defined
at CastPlayer.initializeCastPlayer (CastVideos.js?=18:179)
at window.__onGCastApiAvailable (CastVideos.js?=18:1643)
at chrome.cast.ha (cast_sender.js:94)

What do I need to fix this issue?