In Bootstrap 1.5.6-v2.0.0 the variables $flag_disable_right and $flag_disable_left are undefined.

ZC 1.5.6c defines these in \includes\templates\responsive_classic\common\ main_template_vars.php on line 26

if (!isset($flag_disable_left)) {
$flag_disable_left = false;
}
if (!isset($flag_disable_right)) {
$flag_disable_right = false;
}
Great template. Thanks for all the work.

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environment Dev: Zen Cart 156c; Apache 2.4.33; PHP 7.3.1; MySQL 5.7.21; Windows 10
environment Test: Zen Cart 156a; Apache 2.4.29; PHP 7.2.4; MySQL 5.7.24; Linux 4.15.0

packages / add-ons:
ckeditor ; clone template 1.2.0; payment module fee; Direct bank Deposit V1.5.revised; zencart155 securepayxml (modified); ozpost v4.2.7;
ceon_back_in_stock_notifications.9 (modified); export_shipping_information_V1.3.5 (modified);
edit_orders-4.3.5; master password 4; admin log in as customer; ZCA bootstrap template-for-156-v2.0.0c; image checker 2.0; sales report 3.2.2; email archive manager 1-8e; zenNoncaptcha v0.5