Description

Inhttps://discourse.jupyter.org/t/jupyterlab-not-remembering-trust-for-notebooks/7869, a user told about how they had difficult persisting trust state in a new notebook. I tried trusting a new notebook, and could not get JLab to do so.

Reproduce

In JupyterLab 3.0.7 in a clean environment (but also in latest JLab 2 or JLab 1, from my experiments):

1. Create a new notebook and evaluate a few cells and have a few blank cells
2. Check the trust status in the status bar. For me, it says for example "Notebook not trusted: 3 cells of 4 cells trusted", where I have 4 cells and one of them is blank.
3. Run the "Trust notebook" command from the command palette, and see that the trust status bar icon still says the same thing.
4. Close and shutdown the notebook, then open it again. None of the cells will be trusted (which IIRC is expected behavior if at least one cell was untrusted when saved)
5. Run all the cells and delete the empty cells. Then the trusted status bar icon shows the notebook is trusted.

Expected behavior

Running all the cells in a notebook should trust all the cells (and thus trust the notebook as a whole). Probably blank cells (both input and output) should be considered trusted by default.

Context

• Operating System and version: macOS Catalina
• Browser and version: Firefox 85
• JupyterLab version: 3.0.7

It does not look like there are any relevant errors in the js console or in the server log.