replace untrusted HTML after a jupyterlab notebook by a small message

[jangenoe]

When a Html5 movie is generated in jupyterlab, it is rendered perfectly as cell output as long as the file is open.

HTML(animation.ArtistAnimation(fig, ims, interval=50, blit=True,repeat_delay=1000).to_html5_video())

When the file is subsequently saved and reopened again, the cell output seems to be gone, but it is not.
Just trusting the notebook renders the cell perfectly again as it was before.

I understand this is due to a lack of trust in html code.
Could the blocked rendering of HTML output after opening an existing file not be replace by a small message:
“HTML output not rendered, as this notebook is not trusted. Please trust the notebook to render this cell”?

This would prevent me from rerunning cells unneeded, as some of these movie calculations can take a lot of time.

[jangenoe]

The issue started first by
Harper357 is similar and could be merged.