Hi,
I wanted to share some knowledge. So I’ll answer my own question, if that’s permitted.
So, I was getting: http://192.168.X.X:8123/frontend_latest/a165dd73e19a69791eb4.chunk.js:629:478 Uncaught TypeError: Cannot read property 'some' of undefined
everytime I switched over a specific tab on the Lovelace UI. I could also see a message on the bottom saying:
I searched on Google, but found nothing. Upon debugging and struggling for a coulpe of hours, I figured it out.
It occurs when you’re trying to access a domain (group, device, etc) that doesn’t exist.
Example:
In lovelace-ui.yaml you have a entity called: “group.downstairs”, but that group doesn’t exist in the groups.yaml. Or similar.
This error occurs in Chrome Browser when you read a property or call a method on an undefined object . Uncaught TypeError: Cannot read property of undefined error is probably easiest to understand from the perspective of undefined, since undefined is not considered an object type at all (but its own undefined type instead), and properties can only belong to objects within JavaScript. There are a few variations of this error depending on the property you are trying to access. Sometimes instead of undefined it will say null.