Add existing template part only shows 10 template parts. Search doesn't find the rest

[bobbingwide]

While documenting the core/template part Footer variation I noted the following:

1. Choose existing only offers 10 template parts.
2. Customized template parts appear first, even if they're overridden by a newer .html file.
3. The search doesn't find the others.
4. If you search for an item that's listed the filtered selection list includes the theme name.

In Fizzie there are currently 28 template parts.

Raising this here before I look for Gutenberg issues.

Only 10 template parts listed.

Category-description shows the darker green background for the Term description block and the shortcode that the Term description now replaces in the .html version.

<!-- wp:group {"textColor":"greeny","style":{"color":{"background":"#cfdbc7"}}} -->
<div class="wp-block-group has-greeny-color has-text-color has-background" style="background-color:#cfdbc7">
    <div class="wp-block-group__inner-container">
        <!-- wp:query-title {"type":"any", "level":2 } /-->
        <!-- wp:term-description /-->

    </div>
</div>

Theme name appearing in the search results

[bobbingwide]

Template parts can now only be added in the Site Editor. The limit of 10 has been resolved.

It would appear that the documentation I produced a long time ago ( for core/header and core/footer ) is probably not reproducible.