[TYPO3-english] Problem "You cannot view this content in a frame"

[Andrea Rossetti]

Hi,
I've successfully installed typo3 on my ubuntu 16.04 xenial, but when I login as admin user on the right part of the browser Windows I have the following message:

"You cannot view this content in a frame There should be content here, but the publisher doesn't allow it to be displayed in a frame. The purpose is to protect any information you enter into the site. Test Open in another window".

The text "Test Open in another window" is a clickable link and if I click it, the content are opened in another tab of the Windows browser.

How can I solve this problem?

Thanks.