iFrame that custom app lives inside of is sandboxed. When trying to open a pdf link inside of the custom app, the pdf tries to open in a new tab but does not display anything, due to Chrome's pdf plugin not being allowed due to sandbox attributes of FreshDesk custom app's iframe.

Is it possible to get reference to the iframe from within the custom app and set allow-popups-to-escape-sandbox attribute? If not is there another work-around that will allow opening a pdf link from a custom app?