I tried setting the CSS “pointer-events:none” on the canvas in @ozRocker demo, this CSS property is meant to “pass through” the clicks to the elements below, but it didn’t work for the iframe.
I thought it might be the case because of security concerns - you don’t want an evil website to put an iframe of some page (assuming a website mistakingly allows the page to be loaded from a frame) and then put a div on top of it, hiding what the user is really clicking, fooling the user into making evil actions.
But looking at the demo @Cstfan linked, it seems to me the only trick there is to set the pointer-events none on the canvas, and there it works fine. So, I guess there is no security concern, and I’m missing something here.
If any of you got the mouse clicks to pass to the iframe, please do share!