Page with page template not using template in Preview

I am using a page template created by myself, which is showing and working correctly in page backend. It also works on the front end.

The problem: Preview shows the normal “page.php” instead of using the template page.
Any idea why this happens? I have never had this problem before.
The template is called “page_temp_news.php” and is setup correctly and working so far.

Using latest wordpress 4.2.2.
nginx server.

Thank you!

AD

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