icekemia@ Thanks for the issue.

Tested this issue on Windows 10 on the reported version 68.0.3440.106 and the latest Canary 70.0.3527.0 by following the below steps.

1. Launched Chrome and navigated to the give codepen link: https://codepen.io/anon/pen/oPvwBz
2. Couldn't observe any resources loaded in the iframe and the same behavior is observed on Firefox.
Attached is the screen shot for reference.

Request you to check and confirm if anything is missed from our end in triaging the issue.
Also request you to provide a screen cast of the steps followed to reproduce the issue which will help in better understanding.

Thanks..

Deleted: 875642.PNG 74.4 KB

	875642.PNG 74.4 KB View Download

Hi,
i also found an error with fullscreen video, this error occurs when the video is a child of an iframe inside an iframe. 

Example:
https://jsfiddle.net/EMLilianaIturribarria/aq5dx8co/

Js Fiddle already wraps my iframe with an iframe.
if you check the iframe src in isolation on clicking watch this will toggle fullscreen.
however that doesnt work if it's inside an iframe.

@liliana, try adding allow="fullscreen" attribute to your iframe

Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

@icekemia, note we are still asking for confirmation of our test method in comment #2.

Reporter,
I think https://codepen.io/anon/pen/oPvwBz doesn't represent the issue because it has <base> and window.location.protocol is unrelated to base URL computation.  Would you provide another reproduction case please?

http://jsfiddle.net/n0gdh5y4/5/ linked in  Issue 484930  still works correctly.

Sorry if it tooks so long, our test tag had expired and we couldn't add real test.
You can check the following testpage https://goo.gl/yoEBAP
It displays fine on Firefox, while Chrome fails loading ima3.js 
If we edit vpaid_adapter.js to load ima3.js with protocol then everything works as it's supposed to.

Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

> You can check the following testpage https://goo.gl/yoEBAP

I saw no problem with this page though it had four cross-site-script-in-document.write warnings about adfscript and bootstrap.js.
I saw no console messages about ima3.js, and I couldn't find strings "vpaid_adapter.js" and "ima3.js" in all source files of the page.

There's no console message about ima3.js. If you check Network tab you
might be able to find vpaid_adapter.js (only after pressing on play button)
This file is calling ima3.js, you can use fiddler to respond with an edited
version of the file.

Il giorno gio 30 ago 2018 alle ore 03:29 tk… via monorail <
monorail+v2.567034358@chromium.org> ha scritto:

Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

> might be able to find vpaid_adapter.js (only after pressing on play button)

Oh, I see.
I confirmed vpaid_adapter.js was loaded in the network tab.

Is there a user-visible behavior difference except for the network tab?

Firefox shows an ad video before "THE RICH MEDIA RIDE" video
Chrome shows "THE RICH MEDIA RIDE" video without an ad

Is this?

Exactly, since ima3.js doesn't load, adv video is not loading as well (and
you can see timeout while waiting for event 'AdLoaded' error in console)

Il giorno gio 30 ago 2018 alle ore 10:36 tk… via monorail <
monorail+v2.567034358@chromium.org> ha scritto:

Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Ok, thanks.

So, the reproducing steps:

1. Open https://goo.gl/yoEBAP
2. Click the play button in the black rectangle
3. Observe

Expected: Playing an advertisement video before "THE RICH MEDIA RIDE" video
Actual: Playing "THE RICH MEDIA RIDE" video without any advertisement video

TE, please do bisect since Chrome 48.

Able to reproduce the issue on Windows 10, Mac OS 10.13.3 and Ubuntu 17.10 on the latest Stable 68.0.3440.106 and the latest Canary 70.0.353.0 as per comment #17.
This issue is observed from M-45(45.0.2410.0) build.
Attached is the screen cast for reference.

Hence this is a Non-Regression issue and marking this as Untriaged for further updates from Dev.
Removing 'Needs-Bisect' label as this issue is observed from M-45 builds. Please feel free to add if needed.

Thanks..

Deleted: 875642-M45.mp4 582 KB

	875642-M45.mp4 582 KB View Download

Here is a minimized reproduction: http://jsfiddle.net/int32_t/oztck57e/5/

The key point is doc2.open() in a srcdoc document context.
The current Chrome behavior conforms to the HTML specification, and other browsers don't. However IMO we should change the specification.  I'll file a specification issue.

Filed https://github.com/whatwg/html/issues/3989