extraHeaders doesn't work when using chrome started with --headless

I’m using chrome-launcher in node to start a chrome instance with the chrome flag --headless set. I’m then using the npm module version of lighthouse and passing it this chrome instance’s port to use. When setting extraHeaders it will only work if I don’t pass the --headless option to chrome launcher. If I remove it, the headers are sent fine to the server, if I enable it my headers are missing even though the headers show fine in the report.json under runtimeConfig.extraHeaders.

What further confuses me, is if I don’t use the lighthouse npm module, and instead use the cli (bypassing the need for chrome launcher) and I pass the --extra-headers argument it also works fine and sends the headers correctly.

I’m using the current version of lighthouse.

[patrickhulce]

@santoshjoseph99 --extraHeaders is a LH flag, not a chrome flag 😃

It seems like pwmetrics passes the flags straight through to LH, so you should be able to do

const options = {
  flags: {
    extraHeaders: {Cookie: 'monster=blue', 'x-men': 'wolverine'}
  }
}

seems like the original topic of this issue has been resolved though, so I’ll go ahead and close this.

[zackiles]

@patrickhulce sorry for the confusion.

I’ve confirmed it is not working passing --headless through the CLI like you’ve described. You can close this issue and I’ll follow up with the Chrome team. Thanks for your help!