From what I understand in the default-filters.php file a filter is applied to the ‘get_the_filter’ filter. The callback is for a method called ‘wp_trim_execrpt’. This is found in formatting.php. From there you can see the logic. Hope that helps.
From what I understand in the default-filters.php file a filter is applied to the ‘get_the_filter’ filter. The callback is for a method called ‘wp_trim_execrpt’. This is found in formatting.php. From there you can see the logic. Hope that helps.