Not sure if I should post bugs for the chat plugin in #bugs or not, so move at will.
In 2.8.1 an issue was introduced which breaks the chat plugin, causing a TypeError: this.editorEl is null javascript error. I have found the cause of this bug and made a pull request. Fix bug regarding Chat on stable by communiteq · Pull Request #15954 · discourse/discourse · GitHub
It would be great if this fix could be included in the stable branch. @martin
EDIT PR is merged so this topic can be closed, thank you for the quick response 