I'm currently developing on my own computer, therefore I'm accessing each iframe by providing a path.
That's the problem. Use a local webserver and test via http://
(or https://
) URLs. If you test things you intend as web pages later via file://
URLs, you will get misled.
In this case, your suspicion in your comment is right: It's the Same Origin Policy. Different browsers treat origin null
(the local file system) differently. Chrome disallows access to other windows when your window is loaded from a local file.