Error in the admin: editor.css not being applied

After I build my project, I’m seeing this error in the WP admin, and none of my styles inside editor.css are being applied.

block-editor.min.js?…0b748cf406a8d42e:26 editor/0-css was added to the iframe incorrectly. Please use block.json or enqueue_block_assets to add styles to the iframe.

<link rel="stylesheet" id="editor/0-css" href="https://www.mysite.local/wp-content/themes/sage/public/css/editor.91be5d.css" media="all">

Btw, this is using a new Sage theme with the only altercation being the added CSS to to the editor.css file.

Looks like this solved the error:

add_action('enqueue_block_assets', function () {
    if(is_admin()) {
}, 100);

And in the editor.css for testing I had body .editor-styles-wrapper (copied over from another Sage project.) It was wrong! It should be body.editor-styles-wrapper .

You may also find this example interesting (Sage 10 FSE sample theme):