[JENKINS-75637] Fix System configuration page no longer having breadcrumb navigation

[janfaracik]

See JENKINS-75637.

This PR restores the breadcrumb menu for pages that use breadcrumb-config-outline - currently just the Manage Jenkins > System page in core. To show the menu hover over the breadcrumb item and you'll see a list of the sections on the page.

Also fixes submenus not opening as expected.

Testing done

• List shows

Proposed changelog entries

• Fix System configuration page no longer having breadcrumb navigation

Proposed changelog category

/label bug

Proposed upgrade guidelines

N/A

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Desired reviewers

N/A

Before the changes are marked as ready-for-merge:

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[scherler]

LGTM

[jtnord]

@janfaracik what is the status of this, is there something holdiing it up or an issue with the approach?

[MarkEWaite]

@janfaracik I'm interested in this pull request as a possible backport for the 2.516.1 LTS release. Is there anything I can do to help it move from draft to ready for review?

[janfaracik]

Hey folks.

I've opened up the PR for review - I've given it a spin and it's working as expected, my only issue with it is that the menu doesn't close when you click an item. I didn't see an easy way to fix that without the risk of introducing regressions unintentionally. If that behaviour is fine then this PR seems good to go.

[janfaracik]

Updated this so that the menu now hides on item click. Would appreciate some testing on this to confirm I haven't broken anything -

I've tested:

• Breadcrumb config outline works
• Credentials breadcrumb item works
• Repeatable list dropdown works
• Design Library Menu page - works as expected

[scherler]

I have tested on my system besides some of the points he tested and have found one regression but it is not due to this PR but I guess a general problem with #links type linking where the header will hide the heading

Besides my code change suggestion I think is ready go, i will create a ticket for the above so we can follow on it.

[janfaracik]

I have tested on my system besides some of the points he tested and have found one regression but it is not due to this PR but I guess a general problem with #links type linking where the header will hide the heading

Besides my code change suggestion I think is ready go, i will create a ticket for the above so we can follow on it.

Added a fix for this - thanks!

[github-actions]

Please take a moment and address the merge conflicts of your pull request. Thanks!

[timja]

LGTM, seems fine now.

General UX of it isn't great and I don't think this should really be a thing but there should be better in-page navigation.

[timja]

/label ready-for-merge

---

This PR is now ready for merge, after ~24 hours, we will merge it if there's no negative feedback.

Thanks!

[A1exKH]

LGTM.

[alecharp]

I think we forgot to merge this pull request. I don't have permissions to do so but can you @timja ?

[krisstern]

@alecharp merged