The problem is not uddeIM but the recaptcha library. The problem is that the recaptcha library displays a picture from the Google servers using http but your server displays all content using https. So the error is that unsecure content is displayed on a page that used https.
As the message says, the content from the Google servers should be loaded using https. According to the function call in the recaptcha library the additional parameter "true" should enforce https transfers. If not there might be a bug in the recaptcha lib. I am sorry but when my fix does not work there is nothing more I can do.
uddeIM & uddePF Development
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