Add a Null Check in windowOfDocument
Add a Null Check in windowOfDocument

Add a null check for windowOfDocument. It is possible you can’t access
a window.frame when it is cross-domain. This could happen at any index
in the window.frame so best to check all of them.

Endika/jquery-simulate-ext,j-ulrich/jquery-simulate-ext,j-ulrich/jquery-simulate-ext,Endika/jquery-simulate-ext