Thanks for the report.  Can you be more specific about the repro steps?  I have a few questions:

Should the load in step 1 complete before proceeding, or does it need to be in-progress?

Is the navigation in step 2 in the same iframe or a different one?  Is that expected to interrupt the navigation from step 1?

Is the button in step 3 in the main frame or one of the iframes?

Hi,

In step 1, navigation should finish.
In step 2, it's the navigation within the same iframe, just a different page. Page 1 -> page 2 -> page 3.
In step 3, the button is in the main frame. The two communicate via `postMessage`. Once a message is received, the `window.history.back()` should occur.

Mac triage: assigning to creis@ for followup or further triage.

Here is a link to reproduce what I think is the same issue for me: https://github.com/jimlesch/ChromeIFrameHistoryFail
I am on Windows 10, Chrome version: 66.0.3359.181

I can repro this issue on my machine every time, but on another Windows 10, Chrome 66.0.3359.181 machine I can never reproduce this behavior, and history.go(-1) works as expected inside the iFrame.

Additional Info: I cannot reproduce this issue in the latest Dev channel release of chrome: Version 68.0.3432.3 (Official Build) dev (64-bit) on Windows 10

I'm able to reproduce this on Chrome 67.0.3396.56 on Windows 10.  I posted the steps to reproduce with examples on this thread, I'll include the information here as well.

https://bugs.chromium.org/p/chromium/issues/detail?id=845923#c4

-------

I am able to confirm and reproduce this issue in Chrome 67.0.3396.56 on Windows 10.  When attempting to use window.history.back() or window.history.forward(), nothing appears to happen when inside an iframe from a different domain.  The window.onpopstate event does not fire either.  

I've setup two sites, one on glitch.me with buttons wired up to back(), forward(), and pushState().  These buttons work fine when you view the site here:

https://young-road.glitch.me/

Now, when I embed https://young-road.glitch.me/ inside an iframe on jsfiddle, the forward/back buttons no longer work, and the onpopstate event never fires.  Here is a link to the jsfiddle with the embedded iframe:  

https://jsfiddle.net/9p3nh3aj/

We have a production application which is embedded in an iframe that uses the history API.  It is currently broken in Chrome, but works in all other browsers.  Please let me know if there is any other info I can provide.

After reading https://bugs.chromium.org/p/chromium/issues/detail?id=845923#c4
I have disabled "Site isolation trial opt-out" in chrome://flags/#enable-site-per-process
and the back button starts behaving as expected.

Sorry that this fell through the cracks before!  lukasza@ has a fix in progress in  issue 845923 .

Thanks for the update and the work to fix it.