error: “cannot modify header…” since update

Hello there, I would need help with the following error that occurs since update of the plugin to ver 2.5.6! What could be the reason of this error? Thank you in advance!

Warning: Cannot modify header information – headers already sent by (output started at /home/customer/www/mybrandies.com/public_html/wp-content/plugins/woocommerce-stock-manager/admin/class-stock-manager-admin.php:493) in /home/customer/www/mybrandies.com/public_html/wp-includes/functions.php on line 6362

here are the code parts this error refers to:
line 493 in class-stock-manager-admin.php:

<style type="text/css">
				#wsm_promo_msg {
					display: block !important;
					background-color: #f2f6fc;
					color: #fff;
					border-left-color: #5850ec;
				}

line 6362 in functions.php:

if ( ! did_action( 'wp_loaded' ) ) {
		/**
		 * Filters the list of protocols allowed in HTML attributes.
		 *
		 * @since 3.0.0
		 *
		 * @param string[] $protocols Array of allowed protocols e.g. 'http', 'ftp', 'tel', and more.
		 */
		$protocols = array_unique( (array) apply_filters( 'kses_allowed_protocols', $protocols ) );
	}

• This topic was modified 5 years ago by horiamar.

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