KernelOutput KernelMessaging Example not working!!

[superjcd]

Description

Several examples didn't work, The browser is just not showing any thing, insted came up with a greyed-out looking like below:

And those not working examples(including datagrid example, kernel messaging, kernel output) all used the StackPannel as the widget, wondering if it related.

Reproduce

Take kernel output for instance, just download the codes, and built the extension, cuz my node version seems not compatible, i used jlpm install --ignore-engines to install some dependencies.

Context

• Operating System and version: windows10
• Browser and version: 102
• JupyterLab version: 3.4.2

Browser Output

Console report the following error repeatly, dont know if related to this problem

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[superjcd]

收到了，谢谢

[superjcd]

Recently I found that's not a problem caused by StackPannel, instead it's may caused by SimplifiedOutputArea I guess; And I found a related issue

[superjcd]

Ok, I figured it out, just add the widget to the left or right side; StackPannel seems cannot add to the main area directly now!

[fcollonval]

Closing as resolved in #225