Description
We already have discussed this, but I just want to track the progress on this issue.
If you open sepal_ui or jupyter based applications, closing the sepal tab, doesn't shut down the kernel and therefore it remains as ghost, consuming memory.
The problem happens because voila only shuts down the kernel when the app is loaded in a browser tab and the tab is closed, producing a beforeunload event which sends a beacon: https://github.com/voila-dashboards/voila/blob/9982c78931fd5fbab60b4edc5f00cb353665c9a2/packages/widgets_manager8/src/index.ts#L75, when sepal closes a tab, it doesn't produce that event and therefore the kernel remains alive.
Also, in sepal.io, when the app is launched as independent browser tab, the beacon is not sent properly in Mozilla, I have reported the error here jupyter-server/jupyter_server#1466.