'Shortlink URL' tag missing

Hello, I just updated our staging site to the latest Metatag version of 2.2.3. After doing so and completing the steps at /update.php, I was presented with the following message:

metatag module
Update v2_06_error_page_defaults

The Metatag configuration for 403, 404 page(s) has been updated. Make sure to export the configuration to avoid losing the changes.

So I compared the /admin/config/search/metatag page (and settings in 'Edit' mode) for "403 access denied" and "404 page not found" on the live site (w/ Metatag still at 2.2.2) against the newly updated staging site.

And in most cases, I was able to update settings on the staging site in these areas to match the live site. However, surprisingly, I do not see a 'Shortlink URL' field now.

In comparison, on the live site, I do see 'Shortlink URL' with the value of [site:url] populated (which I believe was a default setting part of the module's initial configuration settings) ...

And to make matters a little more confusing, at /admin/config/search/metatag for both the "403 access denied" and "404 page not found" sections, on the staging site I see this:

canonical_url: [site:url]
robots: noindex
shortlink:

So on that page, the current module seems to be expecting me to set something for this field, while in the 'Edit' mode I'm not able to do so since that field is missing.

Not sure if this is a bug or somehow expected behavior, but I wanted to raise it since it seems there is something amiss here

Thanks for your help,
Jim