Notebook 7.0.0 ignores kernel's help_links property

[culler]

Problem

With Classic Jupyter and Jupyter Lab, when a kernel is selected to be used by a notebook, the kernel's help_links property is read and the contents are used to add kernel-specific items to the Help Menu. This useful feature appears to have been removed from Notebook 7.0.0. Testing with the SageMath kernel, which provides help_links as a property, indicates that the help_links getter is never called when a SageMath notebook is launched.

Proposed Solution

Please consider restoring this feature (or documenting it, if it actually exists in some other form.)

Additional context

[RRosio]

Hi @culler thank you for submitting this issue! Do you see this in JupyterLab 4?

[culler]

Thanks for responding @RRosio. No, I do not see this problem with jupyterlab-4.0.2 installed from pypi. It takes a few seconds, but the Help menu gets populated with all of the links provided by the SageMath kernel.

I am not at all sure this is relevant, but in the index.tsx file for the Jupyter Lab help-extension I see the following code. The part after the comment "// Generate a cache of the kernel help links", does not seem to have an analog in the notebook source tree:

    // Populate the Help menu.
    const helpMenu = mainMenu.helpMenu;

    const resourcesGroup = resources.map(args => ({
      args,
      command: CommandIDs.open
    }));
    helpMenu.addGroup(resourcesGroup, 10);

    // Generate a cache of the kernel help links.
    const kernelInfoCache = new Map<
      string,
      KernelMessage.IInfoReplyMsg['content']
    >(); 

[jtpio]

Thanks @culler for reporting and trying Notebook 7.

Maybe it would just be a matter to include the @jupyterlab/help-extension:resources plugin in Notebook 7 to get these menu entries.

[culler]

Maybe so. I don't know.

But, if so, I would hope that the extension could be enabled by default, or by the kernel, or by somehow configuring the notebook package in advance before distributing it with the SageMath application. It seems less than optimal to expect a new user to know that getting help when using the SageMath kernel requires running a separate enable command for such an extension.

[jtpio]

For reference I opened #6968 which should help fix this issue.

But we'll likely need jupyterlab/jupyterlab#14837 to be merged and released first in JupyterLab.