When saving edits to the footer in editor (beta), saving fails

[garnitchique]

When editing the page template, saving changes made to the footer fails while saving changes to other blocks works. When saving changes to the footer, this request

POST	https://apgtest.dreamhosters.com/wp-json/wp/v2/template-parts/twentytwentytwo//footer?_locale=user

<!-- wp:group {"style":{"spacing":{"padding":{"top":"var(\u002d\u002dwp\u002d\u002dcustom\u002d\u002dspacing\u002d\u002dlarge, 8rem)"}}},"layout":{"inherit":true}} --><div class="wp-block-group" style="padding-top:var(--wp--custom--spacing--large, 8rem)"><!-- wp:group {"align":"full","layout":{"inherit":true}} --><div class="wp-block-group alignfull"><!-- wp:group {"align":"wide","style":{"spacing":{"padding":{"top":"4rem","bottom":"4rem"}}},"layout":{"type":"flex","justifyContent":"space-between"}} --><div class="wp-block-group alignwide" style="padding-top:4rem;padding-bottom:4rem"><!-- wp:site-title {"level":0} /--><!-- wp:image {"id":8,"sizeSlug":"large","linkDestination":"none"} --><figure class="wp-block-image size-large"><img src="https://apgtest.dreamhosters.com/wp-content/uploads/2022/03/Artboard-1-1024x665.png" alt="" /></figure><!-- /wp:image --><!-- wp:paragraph {"align":"right"} --><p class="has-text-align-right">Proudly powered by <a href="https://wordpress.org" rel="nofollow">WordPress</a></p><!-- /wp:paragraph --></div><!-- /wp:group --></div><!-- /wp:group --></div><!-- /wp:group -->

results in this response

418 I'm a teapot