"Kernel usage is missing" after switching sidebar side

[krassowski]

Description

When switching sidebar side of kernel usage panel it does not show the usage information until we switch notebook/main area widget.

Edit: also happens when opening the sidebar item for the first time.

Reproduce

1. Right click on sidebar kernel usage item
2. Click "switch sidebar side"
3. See "Kernel usage is missing"

Expected behavior

We should trigger an update after reattaching the widget.

Context

• jupyter-resource-usage 0.7.2
• jupyterlab 3.6.1

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[jtpio]

Wondering if this could be the same issue as with Notebook 7 at the moment:

[pinksi]

I used to get this error when the ipykernel version of my kernel is < 6.11.0. Maybe we can check if the kernel has correct version of ipykernel.