Customise JupyterLab's interface on TLJH (w/repo2docker)


I have installed TLJH with its repo2docker plugin.
I now want to customise JupyterLab’s interface for all users.

I have found multiple sources saying that it is possible to achieve my goal through the means of an overrides.json file:

JupyterLab User Settings Directory
Setting default user settings on TLJH

I did as those sources said and I attempted, after reloading the hub, to run TLJH with some settings written inside /opt/tljh/user/share/jupyter/lab/settings/overrides.json:

  "@jupyterlab/apputils-extension:themes": {
    "theme": "JupyterLab Dark"
  "@jupyterlab/notebook-extension:panel": {
    "toolbar": [
        "name": "restart-and-run",
        "disabled": true

Unfortunately, JupyterLab’s interface did not change as expected after logging in with an existing user and restarting a Docker container through JupyterHub’s API.

I then tried changing the overrides.json file’s permission to 755.
And I also tried rebuilding the Docker image through repo2docker’s “Environments” tab.
But still no change in JupyterLab’s interface.

Am I missing a crucial step for this to work?

Hi again!

I have no updates to give on this, but I still need to customise JupyterLab’s interface.

Has anyone got an idea what would be missing?
Or is it just not possible in this use case, with TLJH and repo2docker?