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Core components including the Gecko layout engine, the networking library, and most shared application backend code.

Component Default Assignee Default QA Contact
Build Config nobody@mozilla.org build-config@core.bugs
For core build config issues
Cmd-line Features nobody@mozilla.org cmd-line@core.bugs
For problems with command line parameter handling.

Examples: mozilla -console doesn't work. mozilla -ProfileManager doesn't work. mozilla -turbo doesn't work.
Disability Access APIs aaronleventhal@moonset.net accessibility-apis@core.bugs
Description: This component relates to bugs in our support for accessibility APIs on the various platforms. Accessibility APIs allow 3rd party products, such as screen readers used by visually impaired users, to communicate with our content and UI. The APIs we support specifically are MSAA on Windows and ATK on UNIX/Linux (Apple has not yet published specs for an accessibility API on OS X). This component is not for keyboard, focus or any accessibility bugs other than those relating to the APIs we export.
DOM nobody@mozilla.org general@dom.bugs
For bugs in DOM support which do not fit into any other DOM Component. This is the right component for issues with <base href=""> and xml:base.
DOM to Text Conversion nobody@mozilla.org dom-to-text@mozilla.bugs
Bugs involving conversion to html or plaintext, either during saving or during copy/paste. This component is NOT for general copy/paste bugs, for bugs involving save dialogs or writing to files when saving, or for I18n-related bugs; only for problems with the actual text which is saved.
DOM: Abstract Schemas nobody@mozilla.org general@dom.bugs
For bugs in DOM Abstract Schemas Support. This component provides a representation for XML abstract schemas, like DTDs and XML Schemas and how information within the abstract schemas could be applied to XML documents used in both the document editing and abstract schema editing worlds. Note: This specification is no longer being developed, and thus bugs in this component are unlikely to ever be fixed except by removing code.
DOM: Core nobody@mozilla.org general@dom.bugs
For bugs in our DOM Core support. This component deals with the DOM "Node" interface, the basic types like "DOMString", and related issues.

Examples of appropriate bugs: DOMImplementation.hasFeature("Core", "2.0") returns false; Crash with setAttribute.
DOM: CSSOM nobody@mozilla.org general@dom.bugs
For bugs in our DOM Style support.

Examples of appropriate bugs: document.styleSheets doesn't hold missing file:// stylesheets; crash setting element.style.color to 'red'.

This is not the place for most style bugs unless they involve scripting. See the Style System and Layout components.
DOM: Events nobody@mozilla.org events@dom.bugs
For bugs in our DOM Events support. This component deals with event bubbling, event handling, and interfaces such as UIEvent.

Examples of appropriate bugs: cannot cancel 'submit' event; crash when handling a DOMNodeInserted event after inserting a node into anonymous content.
DOM: HTML nobody@mozilla.org general@dom.bugs
For bugs in our DOM HTML support. This component deals with the HTML-specific DOM interfaces such as "HTMLOptGroupElement" and "HTMLLinkElement".

Examples of appropriate bugs: changing HTMLLabelElement.accessKey has no effect; Crash with focus method on form elements.
DOM: Level 0 nobody@mozilla.org general@dom.bugs
This component includes all functionality related to JavaScript manipulation of window, document and navigator objects that are available in Navigator 4.x and earlier, and that was never defined by the W3C.
DOM: Load and Save nobody@mozilla.org general@dom.bugs
For Bugs in Load and Save. This is an API for loading XML documents into a DOM representation and for saving a DOM representation as a XML document.
DOM: Mozilla Extensions nobody@mozilla.org general@dom.bugs
For bugs in our non-standard DOM support. This component covers areas such as XBL or XUL DOM methods and properties that do not fall under the XBL or XUL components.
DOM: Traversal-Range nobody@mozilla.org traversal-range@dom.bugs
For bugs in our DOM Traversal and Range support. This component deals with the TreeWalker and DocumentRange interfaces, for instance.

Examples of appropriate bugs: cloneContents() doesn't keep namespaces;NodeIterator crashes when calling nextNode() after calling detach().
DOM: Validation nobody@mozilla.org validation@dom.bugs
For bugs in DOM Validation support.
DOM: Views and Formatting nobody@mozilla.org general@dom.bugs
For bugs in our DOM Views support. This component deals AbstractView and DocumentView interfaces.

Examples of appropriate bugs: document.defaultView returns 'null'; calling document.defaultView.document crashes.
Drag and Drop nobody@mozilla.org drag-drop@core.bugs
Description: Problems with drag and drop functionality anywhere in the applications.
Editor nobody@mozilla.org editor@core.bugs
For bugs in Mozilla's embeddable editor. If you're encountering a bug with text or rich text editing elsewhere within Gecko-based products, such as within Mail/News, the Location bar, or a dialog box, file it here.

Examples of appropriate bugs: After inserting a image, selecting Undo crashes Composer; After deleting a word, the caret disappears.
Embedding: ActiveX Wrapper adamlock@eircom.net dunn5557@earthlink.net
This is the ActiveX wrapper that is used when people want to embed Gecko in their application on Windows, instead of using IE as the embedded HTML control.
Embedding: APIs nobody@mozilla.org apis@embedding.bugs
The embedding API is the set of functions that an external application uses to host an instance of the layout engine within itself. The embedded layout engine provides services for rendering web content (HTML, XML, CSS, etc).
Embedding: Docshell nobody@mozilla.org docshell@embedding.bugs
Docshell acts as the glue that initiates and monitors document loading and associates documents to their view for rendering. Previously called Webshell.
Embedding: GRE Core nobody@mozilla.org gre@embedding.bugs
Gecko Runtime Environment is the minimum set of files which are required for running applications written to embed the Gecko browsing engine. It contains the core xpcom libraries, nspr library, a set of key XPCOM components and other supporting files.
Embedding: GTK Widget nobody@mozilla.org gtk-widget@embedding.bugs
A GTK widget that allows the embedding of Mozilla into GTK applications.
Embedding: Mac ccarlen@mac.com dunn5557@earthlink.net
Covers issues and bugs specific to embedding in Mac Carbon or Cocoa applications.
Embedding: MFC Embed nobody@mozilla.org mfcembed@embedding.bugs
For problems with the mfcEmbed application or the mfcEmbed components
Embedding: Packaging nobody@mozilla.org packaging@embedding.bugs
This module is comprised of the makefiles and scripts in embedding/config which are used to build the dist/Embed package. Several embedding applications are built from the contents of dist/Embed as well as the packaged version of MfcEmbed.
Error Console nobody@mozilla.org error-console@core.bugs
The Error Console displays errors, warnings and messages from various components including but not limited to JavaScript, DOM, XML, and CSS. This component is for problems with the Console itself and not for browser or web page problems that are noted in the console.
Event Handling nobody@mozilla.org events@dom.bugs
Any strangeness with keyboard typing, mouse actions, focus changes.
File Handling nobody@mozilla.org file-handling@mozilla.bugs
For issues dealing with helper applications, and guessing Content Types when they aren't specified/known (ftp:, file:, jar:, but generally not http:). This component does not cover: backend networking issues, such as those covered by Networking: FTP or Networking: File, nor does it cover the Download Manager which has its own component.
Form Manager dveditz@cruzio.com
The component that captures user data appearing on a form and autofills that data on other forms.
General nobody@mozilla.org general@core.bugs
For bugs in Core which do not fit into other more specific Core components
GFX nobody@mozilla.org general@gfx.bugs
Cross platform rendering interfaces and cross platform base implementations. Bugs that belong in this component are cross-platform problems with painting, such as fonts getting cropped or underlines not getting correctly removed with dynamic effects. Bugs like this that only occur on one platform belong in the appropriate component listed below.
GFX: BeOS nobody@mozilla.org beos@gfx.bugs
Mapping of cross platform rendering interfaces to BeOS platform APIs.
GFX: Gtk nobody@mozilla.org gtk@gfx.bugs
Mapping of cross platform rendering interfaces to GTK platform APIs (both versions).
GFX: Mac joshmoz@gmail.com mac@gfx.bugs
Mapping of cross platform rendering interfaces to Mac platform APIs.
GFX: OS/2 mozilla@kaply.com os2@gfx.bugs
Mapping of cross platform rendering interfaces to OS/2 platform APIs.
GFX: Photon amardare@qnx.com photon@gfx.bugs
Mapping of cross platform rendering interfaces to Photon platform APIs.
GFX: Thebes nobody@mozilla.org thebes@gfx.bugs
Mapping of cross platform rendering interfaces to Cairo APIs.
GFX: Win32 nobody@mozilla.org win32@gfx.bugs
Mapping of cross platform rendering interfaces to Windows platform APIs.
GFX: Xlib roland.mainz@nrubsig.org xlib@gfx.bugs
Mapping of cross platform rendering interfaces to Xlib platform APIs.
History: Global nobody@mozilla.org history.global@core.bugs
This is the global history which tracks all URLs that a user has visited, across all sessions of the browser. This also includes the history window and link coloring. Examples of appropriate bugs: Chrome URLs incorrectly added to global history, Reproducible crash when sorting by Title in History window, misbehaviour in the History sidebar tab.
History: Session nobody@mozilla.org history.session@core.bugs
This is the back/forward history for a particular browsing session. This includes bugs in HTML frame navigation and the navigator.history object. Examples of appropriate bugs: hitting Back or Forward does not take you to the expected page, dropdown lists from Back and Forward buttons are not accurate, crashes, slowness or bloat when navigating using Back and Forward.
HTML: Form Submission nobody@mozilla.org form-submission@content.bugs
This component is for bugs with HTML form submission. For example, "hidden controls don't get submitted to the server".
HTML: Parser nobody@mozilla.org parser@content.bugs
This system consumes content from the web, parses, validates and builds a content model (document)
Image Blocking nobody@mozilla.org image-blocking@core.bugs
For bugs about (un)blocking images from servers.
Image: GFX nobody@mozilla.org image.gfx@core.bugs
Bugs related to the rendering or drawing of images Use the Imagelib Component for issues with decoding.
ImageLib nobody@mozilla.org imagelib@core.bugs
ImageLib decodes GIF, JPEG and PNG images, and provides the decoded data to the Compositor for display. If Seamonkey can display an image when loaded separately from the page, ImageLib is working, and the actual imaging bug exists elsewhere within Seamonkey.

Please take a moment to learn how to submit useful ImageLib bugs before submitting bugs to this component. (If you need help assigning a particular imaging bug, we'll accept it in ImageLib and reassign it for you.)

Examples of appropriate bugs: PNG gAMA chunk ignored; Crashes on GIF w/corrupted frame(merr-01.gif); or PNGs and JPEGs aren't displayed on FreeBSD.
Installer: GRE nobody@mozilla.org gre@installer.bugs
Installer that is called by client products' installers requiring GRE. Manages issues related to installing GRE as a shared set of files.
Installer: MFCEmbed nobody@mozilla.org mfcembed@installer.bugs
The MFCEmbed installer installs MFCEmbed files and calls the GRE installer. In addition to providing a testable MFCEmbed, it serves as a test case for the GRE installer in its role as a client of other installers.
Installer: XPInstall Engine nobody@mozilla.org xpi-engine@installer.bugs
For bugs in the underlying cross-platform installation technology used by the Seamonkey installers. If you encounter an installation failure via a web page, it probably belongs here. Content developers should also report failures of the XPInstall API to this component.

Examples of appropriate bugs: Installer not installing all files; FinalizeInstall() doesn't check or return error codes; or Text from XPInstall confirmation dialog needs revision.
Internationalization smontagu@smontagu.org i18n@core.bugs
Internationalization is the process of designing and developing a software product to function in multiple locales. This process involves identifying the locales that must be supported, designing features which support those locales, and writing the code needed.
IPC darin.moz@gmail.com

The ipc module provides an out of process deamon and a messaging system through which client applications can communicate. Used, for instance, by profile sharing.
Java APIs for DOM ashuk@eng.sun.com dom-apis@java.bugs
A Java implementation of the Core DOM Level 1 Specification. This API allows Java Applets to access and manipulate the Gecko DOM.
Java APIs to WebShell joe.chou@eng.sun.com webshell-apis@java.bugs
This component is for bugs against the Java API wrapper around WebShell.
Java Embedding Plugin smichaud@pobox.com java.jep@core.bugs
For issues with the Java Embedding Plugin (JEP), a default plug-in in all mozilla.org browser products on Mac OS X.
Java to XPCOM Bridge jhpedemonte@gmail.com xpcom-bridge@java.bugs
For bugs with the interoperability between XPCOM components and Java objects.
Java-Implemented Plugins blackconnect@slashcom.com blackconnect@java.bugs
For bugs against the support for Plugins that are written in Java. This is not OJI, nor the Java Plugin (formerly known as Activator)..
Java: Live Connect nobody@mozilla.org live-connect@java.bugs
LiveConnect is bridging code that connects the standard JavaScript API's with Java API's to provide interlanguage calling. Through LiveConnect Java can access and call objects in JavaScript and JavaScript can access and call public methods and data in Java objects.
Java: OJI nobody@mozilla.org java.oji@core.bugs
Pluggable Java API
JavaScript Engine general@js.bugs general@spidermonkey.bugs
The interpreter engine for the core JavaScript language, independent of the Mozilla browser and its object model. Used to embed the JavaScript language in a variety of applications. File ONLY core JavaScript language bugs in this category; file DOM, style bugs to the DOM Level 0 component. Also note that we have a component specific to XPConnect so please use that when appropriate.
Keyboard: Find as you Type nobody@mozilla.org keyboard.fayt@core.bugs
This component covers bugs in the "Find As You Type" (also known as "Type Ahead Find" or "Incremental Search") feature, which allows quick web page navigation when you type a sequence of characters in the body of the displayed page (not in the Location Bar, edit boxes, or other form elements). Sample bugs include: not finding text on a page, not highlighting text, crashing, etc.
Keyboard: Navigation nobody@mozilla.org keyboard.navigation@core.bugs
Covers keyboard shortcuts, access keys/accelerators, and navigation by using the keyboard (not the mouse or other input device).

Examples: Ctrl+W not closing the browser window under Windows. Command+N not opening a new browser window under Mac OS. Alt+left arrow not going to the previous page under Linux. Alt not accessing the menu or access keys under Windows. Also, the debate as to use Alt or Ctrl under linux as the keyboard accelerator key for shortcuts. Requests for additional keyboard shortcuts.
Layout nobody@mozilla.org layout@core.bugs
For triage, reduction, and reassignment to other layout components.
Layout: BiDi Hebrew & Arabic nobody@mozilla.org layout.bidi@core.bugs
Bugs related to Mozilla's implementation of bi-directional (BiDi) language support for Hebrew or Arabic
Layout: Block and Inline nobody@mozilla.org layout.block-and-inline@core.bugs
Core layout and geometry for basic block and line elements. For example, margin collapsing bugs, border rendering bugs, and bugs with the inline box model belong here.
Layout: Canvas nobody@mozilla.org layout.canvas@core.bugs
Bugs with the HTML5 <canvas> element, its XUL sibling, and related rendering contexts.
Layout: CTL prabhat.hegde@sun.com arthit@gmail.com
Covers complex text systems like Thai, Tamil, Hindi etc, as well as ligatures, character/text whose appearance depends on context, and characters with more than one appearance/position. (Note: --enable-ctl is currently disabled by default.)
Layout: Floats nobody@mozilla.org layout.floats@core.bugs
Issues with CSS floats or left/right aligned images. For example, bugs with the 'float' and 'clear' properties belong here.
Layout: Fonts and Text nobody@mozilla.org layout.fonts-and-text@core.bugs
For problems with enumerating and rendering system fonts, glyph substitution, fallbacks when specified font not available and legibility. Bugs with the CSS 'font' properties belong here.
Layout: Form Controls nobody@mozilla.org layout.form-controls@core.bugs
For problems with HTML Form Elements: buttons, images, edit fields, passwords, file controls, submit buttons, selects, and textareas. NOT for file upload dialog problems, those belong in XP Toolkit/Widgets.
Layout: HTML Frames nobody@mozilla.org layout.html-frames@core.bugs
For rendering and layout issues with frames (<iframe>, <frame> and <frameset> elements in HTML).
Layout: Images nobody@mozilla.org layout.images@core.bugs
Bugs related to the layout of images. Use ImageLib for issues with the decoding of images.
Layout: Misc Code nobody@mozilla.org layout.misc-code@core.bugs
For code-level bugs in things like the pres shell, etc.
Layout: R & A Pos nobody@mozilla.org layout.r-and-a-pos@core.bugs
Relative, Absolute, and Fixed positioning, except when printing. If you don't know what this is then please don't move bugs here, instead select "Layout".
Layout: Tables nobody@mozilla.org layout.tables@core.bugs
For bugs in the CSS and HTML table layout and rendering code. For example bugs with the HTML 'rules' attribute or the CSS 'border-collapse' property belong here.
Layout: View Rendering roc@ocallahan.org ian@hixie.ch
Painting problems. If the object is in the right place, but doesn't paint correctly, it's a view system bug. If it paints OK, but in the wrong place, then it belongs in another Layout component. Bugs with the 'opacity', 'z-index', 'overflow', and 'clip' properties usually belong in this component. (In terms of code, this covers the view/ and gfx/src/nsBlender* directories.)
Localization nobody@mozilla.org localization@core.bugs
Localization is the process of adapting software for a specific international market; this process includes translating the user interface, resizing dialog boxes, replacing icons and other culturally sensitive graphics (if necessary) as well as customizing features.
Location Bar nobody@mozilla.org location-bar@mozilla.bugs
This is the type-in history for the Location bar in the browser window. This includes behavior of the autocomplete widget for URIs, as well as the storage and expiration of the entries. Examples of appropriate bugs: URIs incorrectly added to the drop down list, crashes, hangs, slowness when using this feature.
MailNews: Address Book nobody@mozilla.org addressbook@mail.bugs
Problems with the address book backend and shared frontend bits
MailNews: Attachments nobody@mozilla.org attachments@mail.bugs
For problems with mail or news message attachments.
MailNews: Backend nobody@mozilla.org backend@mail.bugs
Problems with RDF data sources and application logic. Most likely, your problem can fit in one of the other components so this component should be rarely used.
MailNews: BiDi Hebrew & Arabic mozilla@kaply.com giladehven@hotmail.com
Bugs related to Mozilla's implementation of bi-directional (BiDi) language support for Hebrew or Arabic
MailNews: Composition nobody@mozilla.org composition@mail.bugs
Problems with the writing a new email or replying to one including using the autocomplete feature. Generally, problems found are within the compose window before sending a message. A few examples: 1. User interface and functionality problems with the html compose window and the plain text compose window. 2. Problems with addressing a mail message or adding an attachment.
MailNews: Database bienvenu@nventure.com database@mail.bugs
Problems with underlying code in storage of address book content and mail/news summary files. If the problem you are encountering is with the user interface of the address book or of accessing mail, then this component should not be chosen.
MailNews: Filters nobody@mozilla.org filters@mail.bugs
Problems with using filters to filter your mail. A few examples: 1. User interface and functionality problems with creating, editing, deleting, using filters. 2. Incoming mail is not filtered properly.
MailNews: Import nobody@mozilla.org import@mail.bugs
Import Mail, Import Mail Settings from third party applications. Also, Import Address Book entries and preferences.
MailNews: Internationalization smontagu@smontagu.org mailnews.i18n@core.bugs
Internationalization is the process of designing and developing a software product to function in multiple locales. This process involves identifying the locales that must be supported, designing features which support those locales, and writing code needed.
MailNews: LDAP Integration nobody@mozilla.org ldap-integration@mail.bugs
Problems with LDAP functionality that relate to mail/news components. For example, performing LDAP queries in the addressbook, LDAP typedown addressing/autocompletion, and LDAP preferences.
MailNews: Localization nobody@mozilla.org localization@mail.bugs
Localization is the process of adapting software for a specific international market; this process includes translating the user interface, resizing dialog boxes, replacing icons and other culturally sensitive graphics (if necessary) and customizing features.
MailNews: MIME nobody@mozilla.org mime@mail.bugs
Problems with parsing the MIME structure and displaying messages. When this problem happens, it's often useful to attach a copy of the mail message generating the problem. If you have Communicator 4.x, you can select the message and save it as an .eml file (just save with the .eml extension). A few examples: 1. The contents of a message do not display properly. Certain items do not show up.
MailNews: Movemail pkwarren@gmail.com movemail@mail.bugs
Problems with getting mail from the user's spool file. (/var/spool/mail/*). This is UNIX only.
MailNews: Networking nobody@mozilla.org mailnews.networking@core.bugs
Problems with general networking issues integrating with libnet. For specific protocol problems, please choose: IMAP, News, POP, or SMTP from the list.
MailNews: Palm Sync bienvenu@nventure.com vseerror@lehigh.edu
This component is for bugs, issues and enhancement requests for Palm Pilot syncing.
MailNews: Printing nobody@mozilla.org printing@mail.bugs
Problems with printing mail messages and address book cards.
MailNews: Profile Migration nobody@mozilla.org profile-migration@mail.bugs
Problems with migrating your profile from Communicator 4.x to the current Mozilla mail. Choose this component if you've verified that the problem you are seeing does not occur when you create a new profile and add the mail or news account you were using with migration.
MailNews: Search nobody@mozilla.org search@mail.bugs
Problems with the mail/news search backend
MailNews: Security nobody@mozilla.org security@mail.bugs
This component covers all bugs that relate to use of cryptography, S/MIME, and SSL issues for MailNews. Or, use this component if you have a MailNews security bug.
MailNews: Simple MAPI nobody@mozilla.org simple-mapi@mail.bugs
File a bug against this component for problems when using the simple MAPI feature. This feature allows a non-messaging application to perform messaging operations, such as send, address, and receive messages.
MathML rbs@maths.uq.edu.au ian@hixie.ch
Mathematical Markup Language
Networking nobody@mozilla.org networking@core.bugs
For bugs in Mozilla's modular networking library (aka "Netlib" or "Necko".) The networking library supplies the software interface that Mozilla uses to access physical transports (e.g. the Internet and local drives), perform URL resolutions, and handle a variety of networking protocols.

Examples of appropriate bugs: URLs with backslash not fetched; URLs starting with a single slash turn into http:///; Cannot access authenticated FTP site.

Networking: Cache nobody@mozilla.org networking.cache@core.bugs
For bugs in the cache, which stores recently accessed data for more rapid access. Includes the disk cache, memory cache, and all cache preferences.

Examples of appropriate bugs: Implement compression of network cache data; or Implement partial HTTP caching.
Networking: Cookies nobody@mozilla.org networking.cookies@core.bugs
A general mechanism which server side connections (such as CGI scripts) can use to both store and retrieve information on the client side of the connection. This refers to HTML cookies; little blobs of data we store and share with sites
Networking: File nobody@mozilla.org networking.file@core.bugs
For bugs in Mozilla's File IO code. This component deals with File specific issues like writing to disk, reading local files, etc Related problems with file:// protocol may also be addressed here.
Networking: FTP nobody@mozilla.org networking.ftp@core.bugs
For bugs in Mozilla's FTP code. This component deals with FTP specific issues like downloading, directory formats, problems with FTP login, or resuming partial downloads, etc.

Examples of appropriate bugs- Problems with multiple occurrences of files in directory listings, corruption in downloading certain files via FTP, etc.

Networking: HTTP nobody@mozilla.org networking.http@core.bugs
For bugs in Mozilla's HTTP networking code. This component deals with HTTP specific issues like pipelining, keep-alive, HTTP proxies, 1.1 issues, redirects, authentication (basic), etc.

Examples of appropriate bugs: Problems with proxy authentication; HTTP redirects looping indefinitely, etc.

Networking: IMAP bienvenu@nventure.com networking.imap@core.bugs
Problems with receiving mail when your mail account is set up for IMAP. This component should be chosen if you've verified that the receiving problem is specific to IMAP protocol. A few examples: 1. Interoperability problems with IMAP servers (i.e. folders, naming conventions) would fall into this component. 2. Using the IMAP delete model
Networking: JAR nobody@mozilla.org networking.jar@core.bugs
For bugs relating to the jar protocol handler, .jar file handling, and .jar directory browsing.
Networking: News nobody@mozilla.org networking.news@core.bugs
Problems with posting to or reading newsgroups, adding news servers. If you are having problems adding a newsgroup or a news server, you should choose the "Subscribe" component from the list.
Networking: POP nobody@mozilla.org networking.pop@core.bugs
Problems with receiving mail when your mail account is set up for POP. This component should be chosen if you've verified that the receiving problem is specific to POP protocol. Deleting messages to the trash folder would also fall into this component.
Networking: SMTP nobody@mozilla.org networking.smtp@core.bugs
Problems with sending mail. If you have specific problems with the compose window, you should choose the "Composition" component from the list.
Plug-ins nobody@mozilla.org plugins@core.bugs
Plug-ins allow 3rd parties to register a binary library to be called when data of a given mime type is encountered. The plug-in can layout and render the data.
Ports: Qt zack@kde.org ports-qt@core.bugs
Bugs that occur only in the Qt version of Mozilla, but not in other versions like the Gtk one. Sample Bugs: Printing does not work in the Qt port; Images don't show in the Qt port. Unless you know it's a Qt bug, don't file your bug here!
Preferences: Backend nobody@mozilla.org prefs@mozilla.bugs
For bugs in libPref, the backend library that reads, parses, and writes preferences to the user's hard disk. Unless you're a Mozilla developer, your bug probably doesn't belong in this component.

Examples of appropriate bugs: prefs.js on the mac has non-mac style line endings; Large libpref string causes dialogs to crash on Linux; or JS Error at startup reading prefs file on migrated profile.

Print Preview nobody@mozilla.org printing@core.bugs
Problems in the rendering of Print Preview that are not seen when printing the same page.
Printing nobody@mozilla.org printing@core.bugs
Problems printing from this product should be submitted under this component.
Printing: Xprint masaki.katakai@sun.com roland.mainz@nrubsig.org
For bugs in Mozilla's X11 print system. Bugs in the postscript print system should be filed on the Printing Component and not here.
Profile: BackEnd nobody@mozilla.org profile-manager-backend@core.bugs
Problems with the creation, deletion and changing of user profiles during the installation process.
Profile: Migration nobody@mozilla.org profile-migration@core.bugs
Problems with conversion of profiles from previous versions.
Profile: Roaming nobody@mozilla.org profile-roaming@core.bugs
For bugs relating to Profile Roaming support
QuickLaunch (AKA turbo mode) nobody@mozilla.org quicklaunch@mozilla.bugs
For bugs related to the QuickLaunch installer option and preference, which keeps the application resident in memory after all windows are closed, to speed subsequent component loading.
RDF nobody@mozilla.org rdf@core.bugs
Resource Description Framework: Core RDF components, including the in-memory datasource, composite datasource, RDF/XML parser, and RDF resource manager.
Search nobody@mozilla.org search@mozilla.bugs
For bugs associated with the Search button, the Search Results Sidebar panel, and Advanced Search. For bugs involving the "Find" or "Find on Page..." menu items, use Mozilla Application Suite: XPApps.

Examples of appropriate bugs: Keyword searches should open Sidebar and show results; or Search button does not invoke dialog.
Security dveditz@cruzio.com toolkit@security.bugs
For non-crypto security bugs. Or use this general component if you know you have a Browser security bug, but not sure what component to use. Bug will be reviewed for proper component.
Security: CAPS dveditz@cruzio.com caps@security.bugs
Caps is the capabilities-based security system for the browser. Manages principals (entities responsible for a piece of code) and the protected capabilities (the ability to perform a restricted action) that may be enabled for given principals.
Security: PSM kengert@redhat.com psm@security.bugs
A daemon that performs cryptographic operations on behalf of a client application.
Security: S/MIME kengert@redhat.com s.mime@security.bugs
S/MIME is the sending of signed and/or encrypted email.
Security: UI kengert@redhat.com ui@security.bugs
PSM client library
Selection nobody@mozilla.org selection@mozilla.bugs
Selection refers to the user action of selecting all or part of a document and highlighting the selected content.
Skinability nobody@mozilla.org skinability@mozilla.bugs
Issues dealing with Theme Switching and the infrastructure/plumbing of skins. This subsumes the "skins" keyword.

Example: Issues with the Themes Preference Panel, switching from one Theme to another, and skin interaction.
Spelling checker mscott@mozilla.org spelling-checker@core.bugs
For bugs with the spelling checker used by Thunderbird and SeaMonkey.
SQL Jan.Varga@gmail.com irixman+bugzilla@gmail.com
For bugs in Mozilla's SQL support. See the project page for more details.
String nobody@mozilla.org string@mozilla.bugs
The hierarchy of classes related to managing character sequences.
Style System (CSS) nobody@mozilla.org style-system@core.bugs
Bugs in the handling of CSS stylesheets and the computation of style from CSS stylesheets and HTML attributes.

For bugs in the rendering, see the Layout components.
SVG nobody@mozilla.org general@svg.bugs
Bugs against the implementation of the Scalable Vector Graphics (SVG) specification. Reads and renders SVG content.
Tabbed Browser nobody@mozilla.org tabbed-browser@mozilla.bugs
problems in the browser tab features or problems with the widget itself.
Talkback Client jay@mozilla.org chofmann@gmail.com
Problems related to the Full Circle client.

Problems with the server software should be filed in mozilla.org:Talkback.

Testing nobody@mozilla.org testing@core.bugs
Common testing tools for mozilla codebase projects, test suite definitions for automated test runs, tests that don't fit anywhere else, and other fun stuff
Themes nobody@mozilla.org themes@mozilla.bugs
Issues specific to the Classic or Modern themes.

Example: Icons in Modern skin incorrect, behavior of Classic widget incorrect, etc.
Tracking nobody@mozilla.org chofmann@gmail.com
This component is used primarily for "tracking" bugs; bugs used to track a group of bugs.
Viewer App nobody@mozilla.org viewer-app@mozilla.bugs
This is the viewer test app. utilized by Gecko engineers to test the layout engine.
Web Services nobody@mozilla.org web-services@mozilla.bugs
For problems in using SOAP and WSDL to call Web Services from scripts in Mozilla.

Examples: WSDL crashes if no <message> defined; WSDL Proxy callback doesn't allow access to the SOAP Response; Need better facilities to debug SOAP calls.
WebDAV shaver@mozilla.org dmose@mozilla.org
Web Distributed Authoring and Versioning protocol support. Currently lives in mozilla/extensions/webdav/.
Widget nobody@mozilla.org general@widget.bugs
Cross platform widget interfaces and cross platform base implementations. Bugs that belong in this component are cross-platform problems and API issues. Bugs like this that only occur on one platform belong in the appropriate component listed below.
Widget: BeOS nobody@mozilla.org beos@widget.bugs
Mapping of cross platform widget interfaces to BeOS platform APIs.
Widget: Cocoa joshmoz@gmail.com cocoa@widget.bugs
Mapping of cross platform widget interfaces to Mac Cocoa APIs.
Widget: Gtk nobody@mozilla.org gtk@widget.bugs
Mapping of cross platform widget interfaces to GTK platform APIs (both versions).
Widget: Mac joshmoz@gmail.com mac@widget.bugs
Mapping of cross platform widget interfaces to Mac platform APIs.
Widget: OS/2 mozilla@kaply.com os2@widget.bugs
Mapping of cross platform widget interfaces to OS/2 platform APIs.
Widget: Photon amardare@qnx.com photon@widget.bugs
Mapping of cross platform widget interfaces to Photon platform APIs.
Widget: Win32 nobody@mozilla.org win32@widget.bugs
Mapping of cross platform widget interfaces to Win32 platform APIs.
Widget: Xlib roland.mainz@nrubsig.org xlib@widget.bugs
Mapping of cross platform widget interfaces to Xlib platform APIs.
X-remote blizzard@mozilla.org blizzard@mozilla.org
X-Remote Client and Server
XBL nobody@mozilla.org xbl@core.bugs
The Extensible Binding Language, used to bind new behavior and new content to XUL and HTML elements.
XForms nobody@mozilla.org xforms@core.bugs
For bugs with XForms support. This covers all XForms issues including parsing, data model, form controls, and submission.
XML nobody@mozilla.org xml@core.bugs
For bugs in our XML handling. For example, parser errors, or errors in wellformedness error reporting.
XP Miscellany nobody@mozilla.org brendan@mozilla.org
COMPONENT RETIRED. Please do not file bugs here. For cross-platform, code-level bugs that lack a more appropriate component.

Examples of appropriate bugs: nsCString::Append(PRUnichar) ends up calling CopyChars2To2; or nsCString::Append(PRInt32 aInteger, PRInt32 aRadix) uses sprintf()
XP Toolkit/Widgets jag@tty.nl xptoolkit.widgets@core.bugs
XPToolkit includes a User Interface (UI) widget set consisting of menu bars and menus, toolbars and toolboxes, titled buttons, trees, tab widgets, scrollbars, splitters, progress meters, and boxes. Use this category for file picker, color picker, font picker and dialog/window bugs, too. XP Toolkit also accepts bugs relating to copy/paste, drag & drop, key bindings, the clipboard, and focus issues. All bugs concerning skins should use the "Skinability" component.

User interface widgets that are part of a web browser's content (such as web forms) are actually handled by a separate toolbox --- rather than XP Toolkit --- and should be assigned to HTML Form Controls.

Examples of appropriate bugs: Scroll bar disappears when you shrink window; Mouse wheel scrolling broken under Linux; or Horizontal scroll bar flickers mid-screen during window resize.

NOTE: Please use "Keyboard Navigation" component for key cmd problems.
XP Toolkit/Widgets: Menus nobody@mozilla.org xptoolkit.menus@core.bugs
For bugs in the cross-platform menu infrastructure, including the display and behavior of pop-up menus, pull-down menus, and context menus. (Pop-up menus that are part of a web page's content should be assigned to HTML Form Controls.)

Examples of appropriate bugs: Command key symbol is missing from Mac menus; or Context menus pop up in wrong location.
XP Toolkit/Widgets: Trees Jan.Varga@gmail.com xptoolkit.trees@core.bugs
For bugs in the cross-platform tree widget.

Examples of appropriate bugs: Scrolling w/arrow keys unpredictable in tree; Sorting tree when row selected causes crash; or Selecting an open tree item selects all of the children.
XP Toolkit/Widgets: XUL nobody@mozilla.org xptoolkit.xul@core.bugs

For bugs in the XUL language. (XUL is an XML-based language which specifies Mozilla's user interface.)

If you're not actually writing XUL code, this is probably not the right place for your bug.

Examples of appropriate bugs: Duplicate window ID causes infinite loop; or Scrollbars disappear after loading XUL document
XPCOM nobody@mozilla.org xpcom@core.bugs
This is the basis of our component technology; this covers the mozilla/xpcom source directory and includes the "repository". Unlikely a tester would be able to tell there was an XPCOM problem specifically.
XPCOM Registry nobody@mozilla.org xpcom@core.bugs
The persistent registry used by xpcom.
XPConnect nobody@mozilla.org xpconnect@core.bugs
Facilitates calling between JavaScript and XPCOM components.
xpidl nobody@mozilla.org xpidl@core.bugs
The tool that translates IDL into XPCOM header files and Java script stubs.
XSLT nobody@mozilla.org xslt@core.bugs
For bugs on Mozilla's XSLT support. See the project page for tips on testcases and commonly encountered legacy problems.
XTF alex@croczilla.com xtf@core.bugs
eXtensible Tag Framework