diff --git a/src/wp-includes/html-api/class-wp-html-tag-processor.php b/src/wp-includes/html-api/class-wp-html-tag-processor.php
index c619806525..5e2ee114ae 100644
--- a/src/wp-includes/html-api/class-wp-html-tag-processor.php
+++ b/src/wp-includes/html-api/class-wp-html-tag-processor.php
@@ -3197,6 +3197,12 @@ class WP_HTML_Tag_Processor {
 			 * @see https://html.spec.whatwg.org/#attributes-3
 			 */
 			$escaped_new_value = in_array( $comparable_name, wp_kses_uri_attributes() ) ? esc_url( $value ) : esc_attr( $value );
+
+			// If the escaping functions wiped out the update, reject it and indicate it was rejected.
+			if ( '' === $escaped_new_value && '' !== $value ) {
+				return false;
+			}
+
 			$updated_attribute = "{$name}=\"{$escaped_new_value}\"";
 		}