Original issue was not due to problem setting command line flags.

The original issue may not, but I still suspect this bug is happening. Tim was setting his local phone to run Telemetry & got the login screen all the time, which is a sign that Telemetry flag setting wasn't going through.
I guess we need people to fix the issue of Tracing metadata no longer shows CHrome flag to confirm this.

I have observed same issue with --browser=android-chromium.
I see error: "Unsupported page action: Synthetic scroll not supported for this browser". This is not happening with android-content-shell.
And adb tool used by telemetry and forwarder are same in my local environment.

Any known fix for this issue please?

I recently landed https://codereview.chromium.org/2954923002/ which should have fixed one of the reasons this was happening.

If you still see the issue please provide repro instructions and I'll investigate.

I'm also running into this issue.

Charlie, have you been able to figure out some repro steps? Or does it happen somewhat randomly?

I set up a new Nexus 5X yesterday to run on Telemetry with Chrome updated to stable.

I was trying to test typical_10_mobile recorded on WPR go with telemetry with:

tools/perf/run_benchmark power.typical_10_mobile --device=<my_device> --browser=android-system

The browser would boot up, but would be stuck at the screen asking me if I'm okay with Chrome collecting my usage information.

(The reason I assume this is related is because I think that we bypass that screen by running Chrome with a specific bypass flag.)

Which Android version? Does it consistently fail like this?

And yep those extra Chrome screens are a sign of flags not making it to the browser.

Charlie is out at the office. Ahsley: do you mind letting Juan knows the version of A1 test phone in the office?

Note, Charlie mentioned a N5X phone.

Sorry I totally missed this
There appear to be 2 Android One test phones and a N5X on Charlie's desk (I think only the N5X has battery power at the moment). Is there a particular one you want the version of? Or all three?

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