Switching from text to visual breaks some html

This is a wonderful and very useful plugin as much of my site is too complex for blocks.

However I have this problem. On some pages which I converted to blocks, but I then want to edit with classic editor it is fine when I use the text editor (for html) however if I inadvertently switch to visual it will often lose some html. (And sometimes the page editor opens on Visual which also causes the issue)

As an example:

If I had a Youtube embed block it looks like this in the html text editor:

<!-- wp:embed {"url":"https://youtu.be/nF6HQuiWi9E","type":"video","providerNameSlug":"youtube","responsive":true,"className":"wp-embed-aspect-16-9 wp-has-aspect-ratio"} -->
<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">

</div></figure>
<!-- /wp:embed -->

However after switching to Visual it changes very subtly (some line breaks have changed)

<!-- wp:embed {"url":"https://youtu.be/nF6HQuiWi9E","type":"video","providerNameSlug":"youtube","responsive":true,"className":"wp-embed-aspect-16-9 wp-has-aspect-ratio"} -->
<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio">
<div class="wp-block-embed__wrapper">https://youtu.be/nF6HQuiWi9E</div>
</figure>
<!-- /wp:embed -->

This results in the video not displaying on the page.

Can anyone please help?