This page needs a technical review from the Mozilla QA Team in Q4 2014. (Assigned to Aaron Train.) This article has been created from this page from QMO: Bug Verification Day

Every Wednesday,
#qa channel,

Why: One of QA responsibilities is to validate that fixes in the browser don't yield any regressions and verify that bugs are properly fixed. In order to do this and provide community members a new area of involvement, we organize a Bug verification day on a weekly basis, every Wednesday.

How: Choose a bug from the lists in the Bug Verification wiki and follow the detailed steps below to begin your verification.

How to Verify Fixed Bugs:

  1. Read the description and comments in the bug to understand the problem.
  2. If you don’t understand the bug, comment it asking for whatever additional details you need to understand and verify it.
  3. Try to reproduce the bug on a build that is known to be broken (usually any Nightly starting from the day the bug was filed to the day the bug was fixed - when the link to "" is provided in the bug comments).
  4. If you are able to reproduce the bug on a known broken build, download a version that is thought to be fixed (usually indicated by the status-firefoxN flags and the Target Milestone) and try to reproduce the bug.
  5. Take into consideration that Nightly and Aurora branches receive updates once per day, while the Beta version only updates once a week (which means that you might have to wait a few days to get a build with the fix).
  6. a) If you are still able to reproduce the bug, provide the details of your testing in the bug report and ask if the bug should be reopened.

b) If the bug does NOT reproduce, then you can mark the bug “verified”. Set the “status-firefoxN” (N-Firefox version) flag to “verified” for the version you tested, add a comment indicating the details of your testing. If the bug was verified on all the tracked versions, you can change its resolution to VERIFIED FIXED. Ask someone on IRC for help if you don’t have the rights to change the flags or the resolution. When possible, also do same exploratory testing around the fix to ensure nothing got broken.

Example of bug comment with details of testing:

“Verified on Firefox version 20 beta 6, on Windows 7, 64-bits by following the steps from comment x.

I’ve also tested the following scenarios: y1, y2, y3”


Ask: For any questions or tips, use the #qa channel on IRC. The QA team will be there to help. Mentorship: In case you have never verified a bug or just need someone to walk you through our process, please contact one of our QA Mentors. These are their names and IRC nicks:

If you can't find them on IRC, or don't want to contact them this way, you can just cc one of them on the bug you want to work on and ask for help.

Information which might come in handy:

Link to Firefox builds: (the Nightly section contains the latest Nightly and the latest Aurora builds)

In the Releases section you can find the latest Firefox Release Builds and the Latest Firefox Beta Builds.

How to get the User Agent for a Firefox Build:

  1. Open Firefox (any of Nightly, Aurora, Beta or Release)
  2. Type about:support in the URL bar.

In the Application Basics section you will find the User Agent: e.g. Mozilla/5.0 (Windows NT 6.1; WOW64; rv:19.0)Gecko/20100101 Firefox/19.0

Useful resources: