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Bug Reporting Guidlines for the Mac & Linux builds


In order for the bug reports we receive to be most effective, we need to be able to go through them in a timely manner. That means keeping the number manageable. The primary enemy of this effort is duplicate bugs which waste everyone's time and clog up the system. Unlike some other public bug systems, we do not consider the number of duplicates as an indicator of priority, demand, or seriousness. As a result, there is little to be gained from filing a duplicate bug besides slowing down our ability to produce a great piece of software.

Before you file any bug, search the bug tracker to see if your problem is a known issues (Mac query, Linux query). You can safely assume that huge holes in functionality (such as fullscreen not working) are well known and there's no need to file a bug. If you find the bug is already there, feel free to star it so you can find it later and indicate to us another person is interested in its resolution. If and only if you can't find the bug in the database should you consider filing a new one.

If you have any questions about whether or not you should file your bug, feel free to visit #chromium on and ask the community. We'll be more than willing to help you out.

Steps to take before filing a bug:

  1. Try searching for the bug on the Chromium bug tracker, someone may already have reported it.

  2. Try to formulate a reduction, i.e. the minimal set of steps to reproduce the problem.

Example of a good bug report:

Chrome Version : URLs : Other browsers tested: Safari 4: OK Firefox 3.x: OK IE 7: OK IE 8: OK

Chromium : FAIL What steps will reproduce the problem? 1. Launch Chrome 2. Load 3. Click on the picture of the elephant in the top right corner.

  1. All buttons in the Chrome UI turn pink. What is the expected result?

Color of Chrome UI shouldn't change. What happens instead?

My UI Turns Pink. Please provide any additional information below. Attach a screenshot if possible.

System Configuration: Mac OS X 10.5.6 on a PowerMac with 4 gigs of RAM; I use the Swedish-language UI.

Console Output:

5/22/09 2:13:02 PM [0x0-0x12c92c8][67080] LEAK: 27 CachedResource

5/22/09 2:13:02 PM [0x0-0x12c92c8][67080] LEAK: 287 WebCoreNode

5/22/09 2:13:02 PM [0x0-0x12c92c8][67080] Leak 1 JS wrappers.

5/22/09 2:13:03 PM [0x0-0x12c92c8][67080] [67080:19971:1315528366186335:ERROR: /Users/Shared/foo/chrome/src/chrome/src/chrome/plugin/] Not implemented reached in bool

Screenshot attached.

Walkthrough - What's good about the above bug report:

  1. It contains a clear detailed description of the steps needed to reproduce the bug from scratch, including URLs where appropriate. Be as specific as you can. Saying to "click the link in the page" when there are fifty links is unhelpful. When filing bugs about non-English sites, don't assume the developer understands the language of the webpage.

  2. Results in other browsers are noted.

  3. It explains what you saw happen and what you where expecting to see.

  4. Console output and system configuration are included, Console output in particular can be extremely helpful diagnosing an issue! (on OS X you can see the console output by opening /Applications/Utilities/

  5. A screenshot is attached showing the bug.

Other Important stuff:

On OSX, If you've opted into stats reporting Crash dumps will be saved in ~/Library/Application Support/Chromium/Crash Reports/ please attach the files in this directory when filing reports for crashing bugs they can really help us in tracking down issues.

I can't write code, how can I help?:

One of the best ways people can contribute to an open source project is not by writing code but by helping manage bugs in the bug database. There are many activities that help immensely:

You don't need a PhD in computer science to do any of these, and they make a huge difference to both engineering and QAs ability to effectively triage bugs.