Accessing and changing Voila configuration running as lab extension

Hi, I’m using JupyterLab 3.0.10, provided by a JupyterHub server (jupyterhub-singleuser), with Voilà running as server extension (for example, when I select “View” > “Render Notebook with Voilà”, a new tab opens at base_url/voila/render/notebook). Is it possible to access and change the configuration (VoilaConfiguration) of the running extension? I know that the theme and the template can be changed via the notebook metadata or a url query string, but only these two options.