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Freezes in nbclassic with ipykernel 7.1

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#1,471 3 comments 1 reaction 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
jupyter-notebook, python
Domain
backend

Research direction

Investigate the nbclassic “run all cells” path with ipykernel 7.1, starting by trying to reproduce the intermittent freeze and checking kernel behavior after restarting. Use the terminal and devtools console while testing, and consider the issue resolved when the cause is identified and the freeze is prevented or reliably diagnosed.

Written by the indexing model from the issue text.

Description

A few of us have recently noticed that nbclassic has been freezing randomly when doing "run all cells". It's not something we can reliably reproduce, but it happens to me for instance a few times per day. Restarting the kernel and re-running normally fixes it -- sometimes I have to do it twice.

I can't figure out what's the cause, and aren't sure how to debug. No errors appear in the terminal or devtools console.

Any thoughts about possible causes, or ways I could try to debug this?

Dominant language
Python
Stars
734
Forks
411
Avg merge
1d 2h
Merged PRs (30d)
9

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