I'm trying to add a custom appender to my InnerBlocks component. I followed the example here: https://github.com/WordPress/gutenberg/tree/master/packages/block-editor/src/components/inner-blocks
However, nothing changes when I use this code. Am I missing something or has this functionality just not been released yet?
Here's my code, but it's exactly the same as the example.
<InnerBlocks
renderAppender={ () => (
<button className="bespoke-appender" type="button">Some Special Appender</button>
) }
/>