neoslab

Simple HTTPS automatically detects if your website run properly over HTTPS and fix your website accordingly without any extra useless line of code. Your website will move to SSL within few clicks. This plugin also allow you to enable HTTP Strict Transport Security for your website.
<h3>License</h3>
Good news, this plugin is free for everyone! Since it’s released under the GPL, you can use it free of charge on your personal or commercial site.

Simple HTTPS

Correct your SSL/HTTPS issue within few clicks and enable HTTP Strict Transport Security for your website.

Stefan Kittel

It easily solves the problem of mixed unsafe content.
Once a web page has its contents, such as CSS, JavaScript or graphics loads unencrypted, the browser reports the whole website as unsafe.
This message will appear with this or similar texts “Connection is not secure” and “Parts of this page are not secure. This can e.g. be graphics. “.
Now you can check and correct all posts, comments, plugins and the theme …
Or you simply install “SSL Fixit”. 
Finished. There is nothing to configure.
The plugin simply replaces all http: // in the output with https: //.
However, if you still need unencrypted links, you can not use this plugin. 
But that should / should be there in the meantime only in exceptional cases.

SSL Fixit Plugin for WordPress by Stefan Kittel

A simple plugin to fix the html unsecure mixed content error

Simple HTTPS vs SSL Fixit Plugin for WordPress by Stefan Kittel