Add deprecation warning to Collapsible Listbox example

[smhigley]

Resolves #657

Includes the following two changes:

• Updates the link on the main aria-practices.html page to point to the select-only combobox with a text note
• Adds a deprecation warning to the listbox example page

Preview link for example page

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Preview | Diff

[carmacleod]

Looks good!
Thanks, @smhigley !
Approving whether or not the little suggested change is included.

[mcking65]

@smhigley

The deprecation warning looks good.

I think we should also remove the link to the collapsable listbox example from:

• Scrollable Listbox Example
• Example Listboxes with Rearrangeable Options
• Listbox Example with Grouped Options

I'd like to discuss whether we note deprecation in the main document or remove the link. I'm leaning toward removing the link. We might also want to put something in the metadata, perhaps a data attribute on the H1, that would tell the indexing code to ignore it.

Also, what about adding "(Deprecated)" to the beginning of the page title tag and the start of the H1? Hmm, maybe that could be the indicator to the indexing script.

[a11ydoer]

APG groupd made a decision to remove deprecated examples on May 4, 2021

[a11ydoer]

@jongund will update APG example index page after @mcking65 merges this issue.

[mcking65]

Note to self:

1. Prepend (Deprecated) to title tag and H1
2. 2. Remove link from main doc and other example pages

[jongund]

@smhigley @mcking65 @a11ydoer
The only review this pull request needs is editorial on the deprecation warning and testing if the updated link works. This should only require two maybe three people. The list of reviewers seems to accessibility testing on all of our platforms. I suggest updated the list of reviewers on this pull request.

[jongund]

@smhigley
I think this pull request should just delete the listbox-collapsible.html reference in aria-practices.html and not add the new reference to listbox-select-only.html.

The pull request that creates listbox-select-only.html should make it's own changes to aria-practices.html and listbox-collapsible.html so the links actually work, otherwise as a reviewer it is confusing.

[smhigley]

@jongund the added link is for the already-existing combobox-select-only example, and the links should work (or at least, they work fine for me in the preview). If people think it'd be better not to have any link there at all, I'm happy to remove it. I do think it makes sense to use this PR to decide what example links to include in the Listbox section.

[jongund]

@smhigley
The link was not working yesterday when I tested, it works today.

[mcking65]

Oops, right change in wrong file :) I'll push a fix for this.

[mcking65]

I'll fix this one too

[mcking65]

OK, Looks good now. Thank you @smhigley!