example block markup for issue PR 54846 in gutenberg

gistfile1.txt

<!-- wp:group {"align":"full","style":{"spacing":{"padding":{"top":"30px","bottom":"30px","right":"30px","left":"30px"},"margin":{"top":"0px"}},"elements":{"link":{"color":{"text":"var:preset|color|white"}}}},"backgroundColor":"header-footer","textColor":"white","className":"is-style-default","layout":{"type":"constrained"}} -->
<div class="wp-block-group alignfull is-style-default has-white-color has-header-footer-background-color has-text-color has-background has-link-color" style="margin-top:0px;padding-top:30px;padding-right:30px;padding-bottom:30px;padding-left:30px"><!-- wp:group {"layout":{"type":"flex","flexWrap":"nowrap","justifyContent":"space-between"}} -->
<div class="wp-block-group"><!-- wp:site-logo /-->

<!-- wp:navigation {"ref":1017,"icon":"menu","layout":{"type":"flex","orientation":"horizontal","justifyContent":"space-between"},"style":{"layout":{"selfStretch":"fit"}},"fontSize":"medium"} /-->

<!-- wp:group {"layout":{"type":"flex","orientation":"vertical","justifyContent":"center"}} -->
<div class="wp-block-group"><!-- wp:buttons {"layout":{"type":"flex","justifyContent":"right"}} -->
<div class="wp-block-buttons"><!-- wp:button {"style":{"border":{"radius":"4px"},"spacing":{"padding":{"top":"8px","bottom":"8px","left":"25px","right":"25px"}}},"className":"is-style-fill-background"} -->
<div class="wp-block-button is-style-fill-background"><a class="wp-block-button__link wp-element-button" href="https://case.test/contact-us/" style="border-radius:4px;padding-top:8px;padding-right:25px;padding-bottom:8px;padding-left:25px">Contact us</a></div>
<!-- /wp:button --></div>
<!-- /wp:buttons -->

<!-- wp:search {"label":"Search","showLabel":false,"buttonText":"Search","buttonPosition":"button-only","isSearchFieldHidden":true,"backgroundColor":"background","textColor":"foreground"} /--></div>
<!-- /wp:group --></div>
<!-- /wp:group --></div>
<!-- /wp:group -->