My dynamic theme stopped working on MacOS catalina

My dynamic theme stopped working when I upgraded to MacOS catalina.
I get these errors:

Could not map contract ID ‘;1’ to CID {1201d357-8417-4926-a694-e6408fbedcf8} because no implementation of the CID is registered.

Unchecked lastError value: Error: Could not establish connection. Receiving end does not exist. background.js:1

sendRequestToSelectedTab moz-extension://e6e4df8b-23b1-704e-8242-80517f934dd2/js/background.js:1

I found the bug. It was a stupid mistake I made myself.