Why does jupyter notebook server keeps crashing when .ipynb files are opened?

I was able to use jupyter notebook 4 days ago. The only thing that changed was there was a firefox version update.

After that the server crashes everytime .ipynb files are opened. Even the directory will have a server error. I tried it both on Firefox and Google Chrome, both browsers will crash the server.

My only kernel is python3 and it always says "Kernel Busy". I tried resetting my pc and the jupyter notebook, but nothing seems to work.

The console showed:

The last 2 lines are causing the crash but I don't know how to fix it

When I type conda install jupyter in the anaconda prompt, I get something before it finishes as shown below. Maybe it might have a cause as to why it is having issues:

I created a new python environment and installed python, matplotlib, pandas, jupyter and it still crashes

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