Before You Report

Make sure it is a jQuery UI bug

Many bugs reported to our bug tracker are actually bugs in user code, not in jQuery UI code. Keep in mind that just because your code throws an error and the console points to a line number inside of jQuery or jQuery UI, this does not mean the bug is a jQuery or jQuery UI bug; more often than not, these errors result from providing incorrect arguments when calling a jQuery function.

If you are new to jQuery or jQuery UI, it is usually a much better idea to ask for help first in the Using jQuery UI Forum or the jQuery IRC channel. You will get much quicker support, and you will help avoid tying up the jQuery UI team with invalid bug reports. These same resources can also be useful if you want to confirm that your bug is indeed a bug in jQuery UI before filing any tickets.

Disable any browser extensions

Make sure you have reproduced the bug with all browser extensions disabled, as these can sometimes cause things to break in interesting and unpredictable ways.

In Firefox, restart in safe mode.

In Internet Explorer, follow these instructions.

In Chrome, enter chrome://extensions in your address bar and disable all extensions.

In Safari, go to Safari -> Preferences -> Extensions and move the slider to “Off”.

Try a newer version of jQuery UI

Bugs in old versions of jQuery UI may have already been fixed. In order to avoid this situation, make sure you are always using the latest release version.

Try an older version of jQuery UI

Sometimes, bugs are introduced in newer versions of jQuery UI that do not exist in previous versions. When possible, it can be useful to try testing with earlier versions of jQuery UI in order to isolate the faulty code. Knowing specifically when a behaviour does not happen can be just as useful as knowing when it does.

Reduce, reduce, reduce!

When you are experiencing a problem, the most useful thing you can possibly do is to reduce your code to the bare minimum required to reproduce the issue. This makes it much easier to isolate and fix the offending code. Bugs that are reported without reduced test cases take on average 9001% longer to fix than bugs that are submitted with them, so you really should try to do this if at all possible.

When You Report

Search First

Chances are high that whatever bug you are experiencing has already been reported at least once, so try doing a couple of searches before creating a new bug report.

If the bug has already been reported, check to see if you can provide any new information that the original submitter did not, such as a reduced testcase, link to a demo, a patch, or details about other circumstances under which the bug occurs.

What To Provide

At a minimum, the following information should be provided in any new bug report:

1. The version(s) of jQuery affected
2. The browser (or browsers) that you are able to reproduce the bug in, including version numbers
3. The operating system (or operating systems) you experienced the bug on.
4. Step-by-step instructions on how to reproduce the issue, including any required system configuration changes
5. A description of what you expect to happen, and what actually happens 

Ideally, you would also include the following:

1. A link to a reduced, working demo/test case that will never move (jsFiddle is good for this)
2. Information on other jQuery versions tested, including whether or not the issue is reproducible there
3. Information on other browsers where the issue does not occur
4. References to the URL of a web server mentioned in your ticket (if any) in the case of a bug involving Ajax or server-side requests which are needed to fully evaluate the issue experienced.
5. A patch (preferably as a link to a GitHub commit or pull request) 6. A link to any relevant discussions, such as forum posts. 

One Bug, One Report

Please do not submit multiple bugs in one bug report. When you do this, they need to be separated by a team member, and that takes away from time that could be spent actually fixing the bug.

Where To Report

Report bugs on the jQuery UI Trac. You will need to register first, but this only takes a few seconds.