Meta Box

https://support.metabox.io/topic/wyiswg-editor-do-not-work-inside-nested-group-on-some-instances/#post-46715

No one will even reply to this unique ID name solution? When can we expect an update? This is a critical bug for me and more and more customers are reporting this issue to me.

I found a temporary solution, but it slows down the editing page. It turns out that the ids for texarea for wysiwig are not created correctly.

<textarea class="rwmb-wysiwyg wp-editor-area valid" rows="20" autocomplete="off" cols="40" name="sw_c_row[6][sw_c_col][1][sw_c_content]" id="sw_c_col_sw_c_content" aria-invalid="false"><div class="h-4 h-lg-1">34 lata wyzwań nauczyły nas, jak być lepszą organizacją, budować silną markę i wspierać naszych partnerów. Poznaj nasza historię.</div></textarea>

In this case I have a clonable group in a clonable group. The textarea gets an id without the name of the parent group and without its sequence number. This creates multiple textarea with the same id, from which wysiwyg is called. Since multiple textarea have the same id, wysiwyg does not start fully for them.

I solved this problem by modifying the wysiwyg.js script for the meta-box.
/meta-box/js/wysiwyg.js
In the file for the transform() function I added a line so that the isInBlock variable always has the value true, which changes the id to unique.

function transform() {
		var $this = $( this ),
			$wrapper = $this.closest( '.wp-editor-wrap' ),
			id = $this.attr( 'id' ),
			isInBlock = $this.closest( '.wp-block, .components-panel' ).length > 0;
			
        isInBlock=true;
		// Update the ID attribute if the editor is in a new block.
		if ( isInBlock ) {
			id = id + '_' + rwmb.uniqid();
			$this.attr( 'id', id );
		}
...

and in the load function I changed the re-render condition to fire not only for Gutenberg

	// Force re-render editors in Gutenberg. Use setTimeOut to run after all other code. Bug occurs in WP 5.6.
		if ( rwmb.isGutenberg ) {
			setTimeout( () => $editors.each( transform ), 200 );
		}else{
			setTimeout( () => $editors.each( transform ), 20 );
		}

unfortunately this forces a re-render for each wysiwyg, which increases the time it takes to load them. But at least it works until a better solution is found.