Investigating UMA chirp alerts is difficult, especially for those which are not caused by any of the following: UMA noise, Chrome version release, our own server binary release. Then it become a mystery of whether it's a google server issue or non-google server issue, whether it's a regression with correlation being ignored or a historical bug, ... Investigating user-filed prod issues has similar experience when the bug is hard to repro. Although it's a little better as you could ask help from the user to repro the case and provide a NetLog.

Open this bug to see if there's any space to improve, ideally, we need support to collect more data from the user to investigate UMA alerts and corner cases. Do we have any tools to support this?

For example, if something similar to a NetLog from the reporting user could be uploaded ahead and fetched during investigation, that will save us a lot of efforts to eliminate noise, and repro the case. We could eliminate user-specific data from the reports if privacy is a concern.