Internal: Blank page when Salesforce dialing-click jack protection

Clickjacking is a technique used that allows a web user to click on something different from what the user perceives they are clicking on, thus potentially revealing confidential information or taking control of their computer while clicking on seemingly innocuous web pages.

Occasionally, clickjack protection can cause the SalesForce iframe to get blocked from the PhoneBurner dial session window:

To disable this the member needs to do the following:

1. Setup > Security (Administer section) > Session Settings.

2.  Scroll down to the heading Clickjack and make sure none of the boxes are checked, except for Enable clickjack protection for Setup pages, and be sure to hit save. 
*SalesForce now requires that you actually contact SalesForce support to disable clickjack protection for Setup pages. I suggest trying turning the other options first to see if issues still occur before contacting SalesForce support