To access the chat playground in Tabby, you need to launch the docker container with the --chat-model flag and also pass --webserver to enable the chat playground. Here's an example command to run the docker container with the chat model and webserver enabled:

sudo docker run -it --gpus all -p 8080:8080 -v $HOME/.tabby:/data tabbyml/tabby serve --chat-model TabbyML/WizardCoder-3B --device cuda --webserver

By adding --webserver to your command, you should be able to access the chat playground in Tabby.