How to report a bug

These guidelines explain how to write a good bug report or feature request in wiki-org>phab:|Wikimedia's bugtracker (see  for more information). Effective bug reports are the most likely to be fixed.

Quick recommendations for reports

 * Be precise
 * Be clear: explain how to reproduce the problem, step by step, so others can reproduce the bug
 * Include only one problem per report

Can you reproduce the issue?
Try to reproduce your bug using a recent version of the software, to see whether it has already been fixed. If the bug is on a wiki site like Wikipedia you could try testing the latest software version on test2.wikipedia.org.

Has someone else already reported the issue?
Use the search box of maniphest>phab:maniphest/|Wikimedia's bugtracker to see if your bug has already been reported. You can also perform more advanced searches on the search>phab:maniphest/query/advanced/|advanced search page.

Reporting a new bug or feature request
If you have faced a bug in a recent version and no one else appears to have reported it, then:
 * 1) Go to phabricator>phab:|phabricator.wikimedia.org and click "Tasks & bugs" in the side bar.
 * 2) Choose "url>phab:maniphest/task/create/|Create task" in the upper right corner.
 * 3) You will be asked to log in (or register) if you have not already done so (see "").
 * 4) Fill out at least the following fields:
 * 5) * Title: A short one-sentence summary that explains the problem (not your suggested solution).
 * 6) ** Good:
 * 7) ** Bad:

Assigned to: You should ignore this field: Developers will set an assignee when they plan to work on the task.

Priority: You should ignore this field: In general, the priority is set by developers who plan to work on the task (see 1>Special:MyLanguage/Phabricator/Project management#Setting task priorities|Setting priorities). Security: Set this to "Security or Sensitive bug" if many users could be harmed by the security problem that you are reporting. Your report will be kept hidden from the public until it is resolved. -->
 * 1) * Description: Full details of the issue, giving as much detail as possible. This can include:
 * 2) ** For bugs:
 * 3) *** Steps to Reproduce: Minimized, easy-to-follow steps that will trigger the described problem. Include any special setup steps.
 * Example:
 * 1) *** Actual Results: What the application did after performing the above steps.
 * Example:
 * 1) *** Expected Results: What the application should have done, if there was no bug.
 * Example:
 * 1) ** For feature requests:
 * 2) *** A description of what you would like to achieve, and why. A [http://interactions.acm.org/archive/view/november-december-2013/user-stories-dont-help-users-Introducing-persona-stories user story] is an effective way of conveying this.
 * Example:
 * 1) ** Please also provide any other information that might be useful, such as:
 * 2) *** the web browsers, skins, or computer systems you've seen the bug on;
 * 3) *** links or diffs to one or more pages where you encountered the bug; or
 * 4) *** whether the problem appears every time, only occasionally, only on certain pages, or only in specific circumstances.
 * 5) * To attach a log file or (but make sure that no confidential data is included or shown), click the Upload File button (a cloud with an arrow) in the tool bar of the Description field.
 * 6) * Select the tags (project(s)) in which you've found the bug:
 * 7) ** Projects are how developers find tasks to work on. To identify the right project(s), use the search function (in the top right) to find its description.
 * 8) ** This could be for example the  project for the wiki software itself, or  for configuration changes on a Wikimedia site (see "").
 * 9) * Subscribers: You should ignore this field: If you know specific users who will be interested in getting notified of this task you can add them here.
 * 1) *** the web browsers, skins, or computer systems you've seen the bug on;
 * 2) *** links or diffs to one or more pages where you encountered the bug; or
 * 3) *** whether the problem appears every time, only occasionally, only on certain pages, or only in specific circumstances.
 * 4) * To attach a log file or (but make sure that no confidential data is included or shown), click the Upload File button (a cloud with an arrow) in the tool bar of the Description field.
 * 5) * Select the tags (project(s)) in which you've found the bug:
 * 6) ** Projects are how developers find tasks to work on. To identify the right project(s), use the search function (in the top right) to find its description.
 * 7) ** This could be for example the <tvar|product-mw></> project for the wiki software itself, or <tvar|product-wm></> for configuration changes on a Wikimedia site (see "").
 * 8) * Subscribers: You should ignore this field: If you know specific users who will be interested in getting notified of this task you can add them here.

Check if your report is complete, then press the "Create Task" button. Your report will now be in the database and somebody will hopefully take a look at it soon.

That's all! Thanks for your help to improve MediaWiki and Wikimedia projects!

Reporting a JavaScript bug
See also: Help:Locating broken scripts

When you encounter a bug that may be related to JavaScript, do your best to [<tvar|url>https://codex.wordpress.org/Using_Your_Browser_to_Diagnose_JavaScript_Errors#Step_3:_Diagnosis</> identify error messages] and copy them into the bug report.

It's especially important to provide all the information you have, because even the system administrators will have zero access to any error log.

If you are unsure whether a feature you are using is based on JavaScript, try [<tvar|url>http://www.alanwood.net/demos/enabling-javascript.html</> disabling JavaScript].

It's always helpful to include a screenshot with your report.

It's often the easiest way to identify which feature you're talking about, and can often provide information which can help narrow down the error.

Take care to hide any information you don't want to share, like other open browsers tabs or minimised chat windows.