WP 4.2, media upload default URL problem

I’ve upgraded my sites to 4.2.1.

In wp-config.php, FORCE_SSL_ADMIN is true. So, the site itself ise accessed via http and the admin interface via https. The site url is set to http://site.com/ in the admin interface (Settings -> General -> Site URL).

After the upgrade, when the admin interface is accessed via https and a file is uploaded in the media library, the link generated for the file is https://site/ where as it should be http://site/ (since the site url setting is http://site/).

This results in a http/https mixed content (when the media is inserted into a post/page content) and the default settings of popular browsers denies showing of mixed content.

If the admin interface is access via http, the link is generated as it should be –> http://site/.

So the FORCE_SSL_ADMIN options becomes unusable unless you can train all your file uploaders to manually change the file url.