Memory issue with lots of classes on Rich Text Field

[jakejackson1]

Description
This problem can occur if a user copy/paste code from another source that includes a lot of class names.

Consider stripping all the classes from the Rich Text field when output in a Core / Universal PDF.

add_filter( 'gfpdf_pdf_field_content_textarea', function( $value, $field, $entry, $form ) {
	$allowed_tags = array_map( function( $item ) {
		unset( $item['class'] );

		return $item;
	}, wp_kses_allowed_html( 'post' ) );

	return wp_kses( $value, $allowed_tags );
}, 10, 4 );

[JurriaanK]

@jakejackson1 I believe my colleague @sandervdwnl reported this issue.
For your consideration: In our custom template, where it is possible to use the textarea field value as a merge tag, we solved it using the new WP_HTML_Tag_Processor (WP 6.2+)

/**
 * Reduce classes of HTML that is being used to generate a PDF up to a maximum of 5.
 *
 * @param string $html PDF template HTML in string format
 * @param array  $form The current Gravity Forms array
 * @param array  $entry The raw Gravity Forms Entry array.
 * @param array  $settings The current PDF configuration array.
 * @param object $Helper_PDF The initialised GFPDFHelperHelper_PDF class
 * @return string $html The updated html.
 */
function reduce_classes_in_html_of_pdf( $html, $form, $entry, $settings, $Helper_PDF ) {

	$processor = new WP_HTML_Tag_Processor( $html );

	// Iterate through all tags.
	while ( $processor->next_tag() ) {
		$classes = $processor->get_attribute( 'class' );
		if ( $classes !== null ) {
			$class_array = explode( ' ', $classes );
			// Limit the number of classes to 5.
			if ( count( $class_array ) > 5 ) {
				$class_array = array_slice( $class_array, 0, 5 );
				// Set the new class attribute value.
				$processor->set_attribute( 'class', implode( ' ', $class_array ) );
			}
		}
	}
	// Get the modified HTML.
	return $processor->get_updated_html();
}
add_filter( 'gfpdf_pdf_html_output', 'reduce_classes_in_html_of_pdf', 20, 5 );