Chat cannot send messages longer than ~385 characters: Websocket message too big

[JosefSchoenberger]

Describe the bug
When sending a message with > ~385 characters, the message is sent to the backend via the websocket, but the websocket is closed with the close code 1009, which indicates that the websocket message is too large.

To Reproduce
Steps to reproduce the behavior:

1. Go to stream/VOD with an active chat
2. Enter a message with ~400 characters
3. Send message
4. Notice that the message never appeared