Regression Testing for 1.6.0

[vikrampm1]

Perform a full regression testing on the following items (1.6.0 milestone) after all are merged into the develop branch. If there are any issues found, please add them as individual comments below for tracking.

• [x] #2
• [x] #4
• [x] #5
• [x] #10
• [ ] #6
• [ ] #8
• [ ] #7
• [ ] #1
• [ ] #3
• [ ] #11
• [ ] #12
• [ ] #13
• [ ] #14
• [ ] #16
• [ ] #17
• [ ] #18
• [ ] #19
• [x] #20
• [x] #22
• [x] #23
• [x] #24
• [x] #28
• [ ] #32

[qasumitbagthariya]

QA Update ❌

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Issue 1: When attempting to update a list without selecting an updated item from the dropdown menu, a fatal error occurs upon clicking the "Update List" button.

https://github.com/mailchimp/wordpress/assets/67687255/c80711b1-08ce-4cdf-a5ba-106af0156681

[28-Jun-2024 11:40:20 UTC] PHP Fatal error:  Uncaught TypeError: count(): Argument #1 ($value) must be of type Countable|array, null given in /Users/sumitbagthariya/Local Sites/mailchimp/app/public/wp-content/plugins/mailchimp/mailchimp.php:695
Stack trace:
#0 /Users/sumitbagthariya/Local Sites/mailchimp/app/public/wp-content/plugins/mailchimp/views/setup_page.php(24): mailchimp_sf_change_list_if_necessary()
#1 /Users/sumitbagthariya/Local Sites/mailchimp/app/public/wp-content/plugins/mailchimp/mailchimp.php(792): require_once('/Users/sumitbag...')
#2 /Users/sumitbagthariya/Local Sites/mailchimp/app/public/wp-includes/class-wp-hook.php(324): mailchimp_sf_setup_page('')
#3 /Users/sumitbagthariya/Local Sites/mailchimp/app/public/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters('', Array)
#4 /Users/sumitbagthariya/Local Sites/mailchimp/app/public/wp-includes/plugin.php(517): WP_Hook->do_action(Array)
#5 /Users/sumitbagthariya/Local Sites/mailchimp/app/public/wp-admin/admin.php(259): do_action('toplevel_page_m...')
#6 /Users/sumitbagthariya/Local Sites/mailchimp/app/public/wp-admin/options-general.php(10): require_once('/Users/sumitbag...')
#7 {main}
  thrown in /Users/sumitbagthariya/Local Sites/mailchimp/app/public/wp-content/plugins/mailchimp/mailchimp.php on line 695

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Suggestion There is inconsistent spacing between Header and Sub-Header, In the shortcode and the Mailchimp widget.

Shortcode

Widget

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