Thanks for the report. 

That's certainly interest, I wonder why headless will interpret this differently. 

It would help greatly if you could find a small example of this happening that you could share here.

As a work around you might look into using Request Interception: https://chromedevtools.github.io/devtools-protocol/tot/Network/#event-requestIntercepted
to block/modify these requests

[mac triage] maybe we need OS=Headless...

@brian.kwon-- Could you please check and try the wrok around steps provided in comment #2 and update the thread .

Thanks!

@dvallet @hdodda So I just tried using this work around.  It seems I need to use Network.continueInterceptedRequest in conjunction with this.  I'm able to alter the header values, but I'm unable to alter the resourceType which I think is the main issue.

As for the small example, I can provide you with the credentials to the site that I'm using, but I prefer not to post it on this board.  Can I e-mail you?

Thank you for providing more feedback. Adding requester "hdodda@chromium.org" to the cc list and removing "Needs-Feedback" label.

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A minimal example that can be made public would be more convenient. But if its not possible (and you are ok with me sharing the information with the team), feel free to email me steps to reproduce

Sorry for the inconvenience, but I'm unable to find a public, minimal example for this issue as I'm not even sure what is causing it.  I've emailed you with steps to reproduce that's quite simple :)

Thanks for the info. 

I can confirm that this is happening in Headless mode on Mac. 

Linux and Windows do not show this performance regressions. 
The network stack should be the same on all platforms, so I'm not really sure why the difference. 


For reference, the warning that is produced on Mac is : 

Resource interpreted as Document but transferred with MIME type application/javascript: "https://s1-powerpoint-15.cdn.office.net/p/s/1685247226_App_Scripts/jSanity.js".

Could you paste the request headers when intercepted, I'm wondering if it could be an issue similar to this one: https://stackoverflow.com/questions/6587393/resource-interpreted-as-document-but-transferred-with-mime-type-application-zip

"{
  "interceptionId": "id-23",
  "request": {
    "url": "https://s1-excel-15.cdn.office.net/x/s/1685221877__layouts/Resources/1033/EwrDefault.css",
    "method": "GET",
    "headers": {
      "Upgrade-Insecure-Requests": "1",
      "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/62.0.3198.0 Safari/537.36",
      "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8"
    },
    "initialPriority": "VeryHigh",
    "referrerPolicy": "no-referrer-when-downgrade"
  },
  "resourceType": "Document",
  "isNavigationRequest": true
}"

These are the params from Network.requestIntercepted for the first instance of the issue.  Seems to be a similar issue as isNavigationRequest is marked as true.

Hi, wondering if there are any updates on this.

This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

Sorry for the inconvenience if the bug really should have been left as Available.

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