MailChimp subscribe URL causes warnings on secure (HTTPS) sites

I added a MailChimp optin form to my HTTPS site with MAB. Unfortunately this causes a browser warning, since it creates a form element with action=”http://..” to the MailChimp list-manage page.

I sent a support ticket to MailChimp to see if I can tweak this in my list settings anywhere, so that the API returns an HTTPS endpoint for subscribe_url_long that MAB is using.

In the meantime, I hacked MAB to set the form-action-url to a protocol-less one by changing lib/classes/ProsulumMabAdmin.php:

$listData = $this->getMailChimpListSingle( $mab['optin']['mailchimp']['list'] );
// Added line, from https://coderwall.com/p/goabcq
$listData['subscribe_url_long'] = preg_replace('#^[^:/.]*[:/]+#i', '//', $listData['subscribe_url_long']);
$mab['optin']['mailchimp']['form-action-url'] = str_replace('subscribe', 'subscribe/post', $listData['subscribe_url_long']);

I’ll post if I hear anything from MailChimp, but thought I should mention it here too in case this could be handled in the plugin in the meantime.

https://ww.wp.xz.cn/plugins/magic-action-box/