Update:

[Unable to provide bisect using 1) Per-revision script as "RuntimeError: We don't have enough builds to bisect" error message is thrown and
				2) Chromium bisect script as 'Report an issue...' option is not available.
Hence, providing suspect manually.)

CHANGE-LOG URL:

https://chromium.googlesource.com/chromium/src/+log/72.0.3603.0..72.0.3604.0?pretty=fuller&n=10000

Suspecting: r605822 ?

@afakhry: Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.

Thank You..!!

+xiyuan@ +rkc@  +antrim@ why sign in doesn't work in an app window here? Is sign in in this landing page important?

Do you get any console error messages?

Not sure what the "Signin" button does, it might try to navigate to Gaia and get blocked inside an app window. I suspect we reach AppWebContentsHelper::OpenURLFromTab [1]. 

It is kind of WAI as we want to limit the ability of feedback app to open a tab. And I don't think this sign-in in help page is important. If we have to support it, we could create a wrapper page in the app window and host the url inside a <webview>, which allows navigation.

[1] https://cs.chromium.org/chromium/src/extensions/browser/app_window/app_web_contents_helper.cc?rcl=7739d6437b6ade5f290cfe3f195e69faccf7d3c6&l=51

The error seen at the console is:

Can't open same-window link to "https://accounts.google.com/ServiceLogin?hl=en&passive=true&continue=http://support.google.com/chromebook/answer/3142217%3Fvisit_id%3D636772957737114635-2404874354%26p%3Dfeedback_confirmation%26rd%3D1"; try target="_blank".


Which matches what AppWebContentsHelper::OpenURLFromTab() gives as you linked above.