My website shows ‘connection is not secure’ on Firefox when I activate a third party theme. Also, all the forms on this theme says: ‘This connection is not secure. Logins
Your site does not have SSL certificate. To protect the users some browsers are giving warning as and when users give an input. You have to purchase SSL certificate to get rid of the problem and the 'http://' will be replaced by 'https://' . I invite to follow the link for more information. https://developer.mozilla.org/en-US/docs/Web/Security/Insecure_passwords