a connection to the notebook server could not be established. the notebook will continue trying to reconnect. check your network connection or notebook server configuration. · Issue #5149 · jupyter/notebook · GitHub
python - Issue connecting to the Kernel in Jupyter notebook - Stack Overflow
python - How does one connect a Jupyter Kernel to VS Code if one does not connect automatically? - Stack Overflow
Kernel stops responding if the kernel is reconnected during code execution · Issue #2633 · jupyter/notebook · GitHub