Can't inspect iFrame nodes

[minig0d]

Extension works fine on the main frame, but doesn't recognize any time you inspect an element within an iFrame.

I tinkered with it, but unfortunately I fear it's above my knowhow.
I suspect it has something to do with the eval context and that either the frameURL needs to be passed or the contextSecurityOrigin needs to be set (or the code needs to be refactored to use the more secure tabs.executeScript method)
https://developer.chrome.com/extensions/devtools_inspectedWindow

Just throwing this out there in case anyone revives this extension as I haven't found a newer one that does the same thing yet :)