- 1 Where to Get Help
- 2 Installing Firebug
- 3 Using Firebug
- 3.1 For Beginners
- 3.2 Opening Firebug
- 3.3 Resetting All Options
- 3.4 Firebug Icon in Firefox 4.0+
- 3.5 Enabling Firebug 1.4+ for specific sites
- 3.6 Enabling Firebug 1.05 for specific sites
- 3.7 How to Enable/Disable Firebug 1.2
- 3.8 Using the Tracing Version of Firebug
- 3.9 Editing Pages
- 3.10 Firebug Console
- 3.11 Firebug DOM Panel
- 4 Firebug Versions
- 5 Installation Issues
- 6 Crashes
- 7 Bugs in Firebug
- 8 Incompatible Firefox extensions
- 9 Contributing to Firebug
- 10 Miscellaneous
Where to Get Help
How do I install Firebug?
Installing from AMO
On AMO you'll find the latest stable release of Firebug, that works on Firefox 2 and 3. Firebug can be found on AMO in here.
Installing directly from Firebug's releases page
Here you'll find the latests betas and alphas from firebug.
- For installation problems, try a new Firefox profile (see below) or contact Firefox Support.
Installing by getting the latest source
Can't wait for the next release? Always want to be up-to-date? Then you can get the latest source code from the Firebug repository.
How to get it to run is described in the Development Setup.
Can I use Firebug on non-Firefox browsers?
Firefox 3.6 and earlier: click the Firebug button in the bottom right corner of Firefox. Firefox 4.0: the Firebug Start button maybe be in the bottom 'add-on' bar or the top 'tool-bar' or you may have removed it. Sorry this was not our design choice.
Resetting All Options
To reset all of the Firebug options to their defaults, open Firebug Icon Menu (upper left corner) > Options > Reset All Firebug Options.
Firebug Icon in Firefox 4.0+
In Firefox 4.0 the status bar got replaced by an (initially hidden) add-on bar. Firebug 1.7 accordingly added it's [Button] from the status bar to the toolbar, though it also kept the icon in the add-on bar. In Firebug 1.8 we now even removed the add-on bar icon by default. If you want the Start Button back at the bottom of Firefox, you have two possibilities to do so:
- Move the Start Button from the toolbar down
- Right-click on the toolbar and choose Customize...
- Click on the Firebug Start Button, drag it and drop it on the empty bar at the bottom
- Close the Customize Toolbar dialog
- Add the previous Firebug icon
about:configin the address bar and hit Enter
- Accept the following warning (if you didn't turn it off before)
- Search for
- Double click on it to set it to
Enabling Firebug 1.4+ for specific sites
Firebug uses a very straight forward activation solution:
- Firebug is disabled on sites by default. If you don't open Firebug while viewing a site, Firebug is not active.
- Firebug is enabled on sites when you open Firebug on that site. This setting is 'sticky': if you stop using a site and return to it later, Firebug will be enabled on that site.
- If you no longer want to debug a site with Firebug, close Firebug on that site with the "Off" button, the right most of three red buttons in the upper right corner.
The panel enablement is completely separate from the site activation. Use the mini-menu on the panel tab to set the panels one by one, or right click on the Firebug Status bar icon to control all of the panels at once. You can enable just the Net panel and or just the Script panel or both. The Console requires the Script panel, so enabling the Console also enables the Script panel. These setting are 'sticky' and remain in effect until you change them.
For more detailed information, see Activation
Enabling Firebug 1.05 for specific sites
To enable Firebug only for some sites you are working on do this:
- Disable Firebug:
- Firefox->StatusBar->(green check or gray dot)->RightClick->Disable Firebug checked
- Navigate Firefox to the site you want to work on.
- Enable Firebug for Site:
- Firefox->StatusBar-(Firefox->StatusBar->(green check or gray dot)->RightClick->Disable Firebug checkedDisable Firebug for ... unchecked.
To get finer control you can use
- Firefox->StatusBar->(green check or gray dot)->RightClick->Allowed Sites
- OR Firebug->BugIcon->AllowedSites
How to Enable/Disable Firebug 1.2
The logic behind enabling and disabling Firebug has been changed in 1.2. Since this version, every panel that could have negative impact on Firefox performance can be enabled and disabled separately. Thus there is no need to disable entire Firebug.
The following panels are activable. Notice that all these panels are disabled by default.
- Net - Network Monitor
A new activation menu has been introduced to make easy to enable/disable appropriate panel. This menu is located directly on the panel's tab (there is a little drop-down next to the tab label).
This menu can be used to enable/disable specific Firebug panel for:
- the current site (e.g. the Enable debugger for www.google.com menu-item)
- all sites (e.g. the Enable debugger menu-item)
Also, if a panel is disabled, its content is replaced by a form that allows one-click activation of multiple panels - for the current site - at once.
See some screenshots of the activation UI here. Source and Extending Firebug
- Firebug Internals (on a real wiki)
- A comprehensive tutorial and a sample XPI for extending firebug.
- A HelloWorld for extending Firebug.
- Readme file for branches of source tree
Using the Tracing Version of Firebug
- First follow the instructions from the preceding section to create a new Firefox profile.
- Install the tracing version from the install page.
- The tracing version will 1.5X rather than 1.5.
- Open Firebug, then open the tracing panel from the Firebug Icon menu (upper left in Firebug)
- In the Tracing window Option tab, set ERRORS on, switch to the Log tab.
- Try your problem page/function.
- Look for error messages in the log. You can export the trace with the button at the top.
- To get help, open an issue report and attach the trace.
- For problems with breakpoints, set UI_LOOP and BP, and SOURCEFILES
- For problems with Console, set CONSOLE and ACTIVATION
- For problems where Firebug UI is acting, set DISPATCH, ACTIVATION, and PANELS
- For crashes or hangs, run from the OS console with this about:config preference true:
Can I save to the source the changes I made to the webpage I'm seeing?
Right now you can't. As John J. Barton wrote on the newsgroup:
Editing in Firebug is kinda like taking out the pickles from and adding mustard to a restaurant sandwich: you can enjoy the result, but the next customer at the restaurant will still get pickles and no mustard.
This is a long requested functionality, so someday it'll be available directly from Firebug. Meanwhile, you can try Firediff, an extension for firebug by Kevin Decker.
How can I output all changes that have been made to a site's CSS within firebug?
That's a feature implemented in Kevin Decker's Firediff.
Does Firebug interfere in any way with jQuery's '$' shortcut?
Although Firebug uses the '$' notation, it doesn't interfere with your code. Sometimes you may have issues testing code in the console, but can easily avoid them by using the jQuery's alternative notation:
I get an error: "console is not defined"
How to Enable Console?
Click on grayed-out console tab. Click on small arrow to see tab menu.
Firebug DOM Panel
What do the different colors of the variables mean?
Bold Black are objects
Not so bold Black are DOM objects
Get in Gray in front means "getter"
Bold green are user functions
Not so bold Green are DOM functions
Bold Red are constructor functions
- Version 1.05: check using Firefox->Tools->Addons->Firebug. Version number on the panel.
- Version 1.1: check using Firebug->BugMenu->About
- Version 1.2+: hover on the Firefox status bar icon for Firebug
- Firebug 1.9 will work with Firefox 6.0 up to Firefox 9.* (or higher)
- Firebug 1.8 works with Firefox 5.0 up to Firefox 7.*
- Firebug 1.7 works with Firefox 3.6 up to Firefox 5.*, see however known issues.
- Firebug 1.6 works with Firefox 3.6
- Firebug 1.5 works with Firefox 3.5 and Firefox 3.6
- Firebug 1.4 works with Firefox 3.0 up to Firefox 3.6 (1.4.4)
- Firebug 1.3 works with Firefox 1.5 (1.3.0) up to Firefox 3.0
- Firebug 1.2 works with Firefox 2.0 and Firefox 3.0
- Firebug 1.0 works with Firefox 1.5 and Firefox 2.0
- Firebug Lite works with IE, Safari, and Opera
Please visit AMO for a full version history.
Installing in a clean profile
To test for bugs regarding interactions with other extensions or corrupted profiles, you should do the following.
Firefox and Firebug re-install rarely fixes problems because the configuration files are not altered on reinstall. So to clear out the configuration files you need to create a new Firefox profile:
- Exit Firefox
- Get to a command line
- Run Firefox with -ProfileManager
$ firefox -ProfileManager
- Create New Profile
- Start Firefox with your new profile
- Load Firebug into this clean profile.
- Exit Firefox
- Get to a command line
- Windows: Start->Run->"cmd" enter
- Run Firefox with -ProfileManager (use quotes around the file name because of the spaces)
"C:\Program Files\Mozilla Firefox\firefox.exe" -ProfileManager
- Create New Profile
- Start Firefox with your new profile
- Load Firebug into this clean profile.
Read more about this on Mozilla Support "Managing Profiles"
Can't Install Firebug on Windows
Sometimes Firebug just won't get installed in Firefox using Windows. The first thing to try is a new Firefox profile above. If that fails you can dig deeper. Here are some recommended actions to take:
- With Firefox closed, locate your profile directory, delete these temporary files, they will be automatically re-created by Firefox:
- Disable any Antivirus or BackUp program you may have running and then install Firebug.
- It may be that some software is stopping Firefox creating the file structures needed for the installation process.
- Run Firefox as Administrator. It may be the same as in reason 2, because firefox doesn't have enough permissions.
- Manually install Firebug.
- This can be done easily, just unzip the XPI (it's a normal zipped file with the extension changed) in your extensions folder, inside your profile. You should unzip firebug's XPI content inside a folder named 'firstname.lastname@example.org'. Do this with Firefox closed.
To get the XPI go to Firebug on Addons.Mozilla.Org, right click on the "Add to Firefox" button and select "Save Link As...".
- Crash means the Firefox program ends and the crash report dialog box appears.
- 64 bit Linux crashes with Firebug 1.5.0
- A Firefox crash is always a Firefox bug and needs to be reported to http://bugzilla.mozilla.org.
- The crash information is available after you let the crash reporter log to Mozilla. You can read the report by using
about:crashesas a URL in a reopened Firefox. This link should be supplied in any bug report; it sometimes takes several minutes for the server to digest the incoming reports.
- You can optionally open a bug report for Firebug, but we cannot fix Firefox crashes. This is true even if the crash only happens when Firebug is enabled. What we can do is to try to circumvent crashes by disabling features. Also see the known issues.
- Crash means Firefox exits.
- Please put "Firebug <your Firebug version>" in the Talkback comment field. If Talkback does not come up, see Installation Issues on this page.
- All crashes are Firefox bugs, all Firebug can do is try to avoid using features that tend to crash.
- Is it possible there is a mexican stand off scenario going on whereby Firebug developers say it's Firefox's problems, and then vice versa? If so something needs to be done to address this stand off.
- There is no such standoff. No one working on Firefox claims that the FF2 crashes are caused by errors in Firebug code.
- Please see https://bugzilla.mozilla.org/show_bug.cgi?id=400618
- If diligent documenting of talkback incidents and corresponding bugzilla entries is needed, I'd like to help. Any thoughts?
- More talkback traces would probably not help at this point. The best way to help would be to create test cases that crashes in the shortest possible wall-clock time. That will help developers pinpoint the problem.
- Use the Mozilla talkback site to look for your Firefox stack trace by searching on Comment "firebug".
Hangs: Firefox or Firebug stops responding
A 'hang' means the program is still running (it did not crash) but it fails to respond to user commands. The causes and diagnosis is completely different from a crash.
Firefox starts but fails to show a user interface
To diagnose these problems we need to print messages from the application to see how far it gets. Here is how we do that:
- Make sure you're not in one of the following conflicting situations:
- if you have ZoneAlarm Pro installed on Windows, in Firefox go to Tools -> Add-ons -> Extensions: you should see "ZoneAlarm Toolbar"; version 184.108.40.206 of the extension conflicts with Firebug user interface, so you need to disable it in order to be able to use Firebug;
- [please report other conflicting situations you happen to find]
- Install the tracing version of Firebug in a new Firefox profile
- Open Firefox in Safe Mode, use URL about:config to add or set these preferences "true"
extensions.firebug-tracing-service.DBG_toOSConsole extensions.firebug.DBG_INITIALIZE extensions.firebug.DBG_DISPATCH extensions.firebug.DBG_ERRORS extensions.firebug.DBG_FBS_ERRORS
- Run firefox from the command line of your operating system. Add command line argument "-jsconsole". If you don't see any output, kill Firefox and try again.
- Copy the output of the program into a file and post it to the Firebug issues list.
Bugs in Firebug
Where Are Firebug bugs reported
- Bugs with test cases: Firebug issues list
- Bugs you are unsure about or that are complex: Firebug newsgroup
- Bugs recently fixed: Firebug blog
Please report bugs, usability issues or suggestions in the issues list or newsgroup. Please do not report bugs in this wiki. Please do not report bugs on other newsgroups.
How do I report a bug?
Please first make sure you read about what to do when you found a bug!
Bug reports are managed via a bug tracker hosted at Google Code:
To report a new one go to the bug tracker and click on "New Issue". Then follow the instructions indicated in the issue template.
As a reminder when you're about to report a new bug:
- Give the version number for Firebug, Firefox and your OS, these are very important. (see the compatibility list)
- Provide a proper test case
- This is of utmost importance!
- A test case is a small example script or page, along with detailed step-by-step instructions on how to reproduce the problem. It helps a lot when trying to understand your problem. Normally nothing will be done regarding the issue until a reproducible test case is available! If you need help: We provide detailed info about how to create a test case.
- Check that you have the issue "starred" so you receive emails when your issue goes in, when we have questions just you can answer or when other folks offer suggestions
Remember this is an open source project: the time you invest in explaining a bug goes a long way toward getting it fixed. Conversely, incomplete instructions without an example will probably be a waste of your time: no one will know what to do with the report and we will just ask for more info. If we don't get feedback from you after waiting for some time it will be closed!
Which error messages from Firebug are a problem?
What do the issue status field mean?
- New is set for a new bug report.
- NeedInfo is set, if we need feedback to start/continue working on the issue. The comment will include the info needed from the reporter.
- Triaged is set after the issue has been read and it has been decided, that it is a Firebug issue. Labels will be added to categorize the issue. Normally these include the probable module and one of the Test-case-needed/available flags.
- Started is set to let others know, that this bug is actively being worked on. (Optional)
- Commit is set, when a fix is committed to Subversion (SVN). A comment will also be added, that includes the revision number of the commit and the committers will have set "Owner" to themselves.
- Fixed is set, if the release is created. All bugs with status Commit are marked as Fixed, the release version number is put in the comment and the issue will also be labelled as fixed. The reporter/users with the same issue should then verify, if the issue is now resolved.
- Verified is set after the reporter/users with the same issue reported, that they tested the fix and it works.
- Duplicate is set, if there is already another bug report on the same subject. The issue number of the other bug report will be provided and future info to the issue should be added there.
- ProbablyWorks is set for an old bug report, which was probably fixed earlier, but no direct action was taken to fix it.
- Works is set for an old bug report, for which the reporter or another user, that had the same issue confirmed, that it was fixed earlier, but no direct action was taken to fix it.
- Obsolete is set, if another change either to Firebug or the user agent made this issue inapplicable or unnecessary.
- InsufficientInfo is set for an old bug report with requests for user info, that was never supplied.
- WontFix is set, when we decided to not take action on this issue either, because it is already working as expected, we think the changes are not needed or the request is invalid. The comment will include the specific reason for this decision.
- UserResolved is set, if the reporter/user with the same issue has found a solution or workaround and no action was needed from the side of Firebug.
- OtherComponent means there are strong reasons to believe, that this problem cannot be fixed in Firebug, but is a problem in another software.
- PlatformFixed is set in the case the user agent team fixed a bug, which also fixes the issue.
Tickets normally follow this path: New -> Triaged -> (Started ->) Commit -> Fixed -> Verified
A special tag "Test-case-available" marks bug reports with test cases. These issues are given priority. If an issue doesn't have a test case, please provide one.
How do I request an enhancement for Firebug?
Requesting enhancements for Firebug is easy. Just start a new issue in the bug tracker, choose "User enhancement request" from the templates list and provide the info needed to implement your feature. Remember to put as much info as possible into the description. Otherwise we need to ask you, if something is unclear. Also test cases and mockups help to understand what you are talking about.
Incompatible Firefox extensions
If you have Sothink SWF Catcher extension installed, please upgrade it to the latest version. This add-on has been upgraded to version 1.4.2. The conflict with Firebug is fixed.
Contributing to Firebug
How can I contribute to documentation?
- Everyone: Edit this wiki. You just need to request an account; the editing is just like at Wikipedia.
- Firebug Working Group Members:
How can I help with a translation?
Firebug is being translated using BabeZilla WTS service. You have to register on the site and then register as a translator for Firebug.
Here is a list of existing translations for Firebug (although you need an account on BabelZilla to see it):
I don't see jQuery request in the Console Panel
- Make sure you are really executing an XHR request. Note that jQuery uses
<script>tags from cross domain JSONP requests (see also issue 4482).