Widgets oddity: sometimes not working

Hi, I’ve got a bit of a strange situation. I’m running a JupyterLab with a reasonably simple Mamba environment (python, jupyterlab, pip - then a bunch of python packages; pandas, panel, bokeh, holoviews and the like), and my results seem flaky.
Once in a while, some “multiple choice” questions, which are panel widgets, will not be responsive. I have also seen a couple of widgets not show up.
Normally, they do work; once in a while they suddenly don’t. I tried “reset workspace” and made sure I stopped all running kernels, but still, sometimes the widgets still seem to misbehave. To make it worse: it all started on a Windows machine (not mine), but I have reproduced it on a Linux (Ubuntu) machine as well.

Note the notebooks I’m working in sometimes are refreshed from the outside. I.e. stop jupyter lab and python kernel; then “git restore /the/notebook/i/was/running.ipynb”, then restart lab.

Should I empty some sort of caching? That’s the only thing I can think of, but I don’t know where to look.