recent change to header.php generates errors in debug log

PHP engine version: 7.2.21
WordPress Core version: 5.2.2

WordPress debug log contained several entries like this:
[09-Aug-2019 15:22:29 America/New_York] PHP Notice: Undefined variable: responsive_options in /var/www/vhosts/mysite.com/httpdocs/wp-content/themes/responsive/header.php on line 153

Original line 153 since version 3.16

if ( ( isset( $responsive_options['site_layout_option'] ) && ( 'full-width-layout' === $responsive_options['site_layout_option'] ) && ( ! ( is_home() || is_front_page() ) ) ) || in_array( $responsive_options['blog_posts_index_layout_default'], $responsive_blog_layout_columns, true ) ) {
// notice how $responsive_options key-value of 'site_layout_option' is tested prior to reference BUT the key-value of 'blog_posts_index_layout_default' is NOT tested prior to reference.

Here is my patch-fix to resolve the logged error condition, which simply wraps the “in_array()” with a set of parenthesis and couples it with a respective isset for the key-value:
if ( ( isset( $responsive_options['site_layout_option'] ) && ( 'full-width-layout' === $responsive_options['site_layout_option'] ) && ( ! ( is_home() || is_front_page() ) ) ) || ( isset( $responsive_options['blog_posts_index_layout_default'] ) && in_array( $responsive_options['blog_posts_index_layout_default'], $responsive_blog_layout_columns, true ) ) ) {

In addition, I would post this report in the help forum on the cyberchimps.com site but my account registration is “still pending approval”.