Disable Fullscreen Editor

add_action(

	'enqueue_block_editor_assets',

	function () {

		$script = "jQuery( window ).load(function() { const isFullscreenMode = wp.data.select( 'core/edit-post' ).isFeatureActive( 'fullscreenMode' ); if ( isFullscreenMode ) { wp.data.dispatch( 'core/edit-post' ).toggleFeature( 'fullscreenMode' ); } });";

		wp_add_inline_script( 'wp-blocks', $script );

	}

);