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Mozilla 0.9.3 Release Notes

These release notes describe system requirements, installation instructions, and known issues for Mozilla 0.9.3. These release notes are updated when we receive feedback, so please check back for new information. Consult our releases page to download the source and the latest version of Mozilla for your platform.

Use the Bugzilla Helper to report bugs. Avoid submitting a duplicate bug report by checking to see if your problem is already a known problem or one of our most frequently reported bugs. The bug reporting guidelines explain how to write a useful bug report that results in your problem being fixed.


What's New
System Requirements
Compatibility Information
Installation Notes
Known Problems
Setting Profiles
Mail and News
ChatZilla IRC Client
International Release Notes
Quality Feedback Agent
A Note For Web Developers
How To Get Involved With Mozilla
Where To Find Other Builds

What's New In This Release

  • Mozilla has made continued stability improvements thanks to talkback data which show that recent 0.9.2 branch builds are more stable than Netscape 4.78. We expect even better results for 0.9.3. If you've been waiting for Mozilla's stability to improve, now is the time to try Mozilla again. Be sure to enable talkback reporting so Mozilla can phone home with debug data if and when you crash.
  • Quick Launch (AKA Turbo Mode) now works with multiple profiles.
  • The Subscribe dialog now lets you search for all newsgroups containing a string when subscribing to newsgroups.
  • The Modern theme has several changes to icons and sidebar tabs.
  • Proxy Auto-Config has been implemented on the Macintosh.
  • There is a new preference for choosing between Windows and Linux scrollbar behaviour when the mouse strays off the scrollbar when you're in the process of scrolling. (Bug 90985)
  • Chatzilla is now localizable.

System Requirements


  • Mac OS 8.6 or later
  • PowerPC 604e 266 MHz or faster processor, or G3/G4
  • 64 MB RAM
  • 36 MB of free hard disk space


  • Windows 95, 98, or 98SE, Windows Me, Windows NT 4.0, or Windows 2000
  • Intel Pentium-class 233 MHz (or faster) processor
  • 64 MB RAM
  • 26 MB of free hard disk space


  • Red Hat Linux 6.x and 7 with X11 R6 [Note: Mozilla is certified and fully supported on Red Hat Linux, but will run on other Linux distributions, such as Debian 2.1 (or later) or SuSE 6.2 (or later). The glibc 2.1 (or higher) library is required.]
  • Intel Pentium-class 233 MHz (or faster) processor
  • 64 MB of RAM
  • 26 MB of free hard disk space


  • OpenVMS Alpha V7.1 or higher
  • DECwindows MOTIF V1.2-4 or higher
  • Compaq TCP/IP Services Version 5.0 for OpenVMS or higher, MultiNet V4.3A or higher, or TCPware V5.4-3 or higher.
  • 65 MB of free hard disk space

    See the Mozilla for OpenVMS Installation Guide and Release Notes at for more information.

Compatibility Information

If you have the Crescendo 5.01 plug-in, you must update to the latest version of Crescendo. Otherwise, Mozilla may crash at startup. (Bug 48110)

If you are using an ATI Rage video card, images are correctly displayed initially, but may not be properly re-drawn when you minimize and maximize or resize the window.

If you use True Type fonts with Mozilla , some characters are displayed as squares. (Bug 51920)

Mac OS

If you have version 4.5 (or earlier) of StuffIt Expander, you may see an error message stating that the archive is corrupted. You can ignore the message and continue with the installation. To get a newer version of StuffIt Expander, go to

If you attempt to run Mozilla on Mac OS using a language pack (such as the Japanese Language Pack) and a Language Kit, all menu bar items will be incorrectly displayed. To resolve this problem, register Mozilla using the Language Register. For instance, if you're using the Japanese Language Pack and the Japanese Language Kit, register Mozilla as a JA application.

If you use the SmoothType control panel instead of Apple's "Smooth all fonts on screen" option in the Appearance control panel, you need SmoothType version 2.1.1 for Mozilla . Mozilla is not compatible with earlier versions of SmoothType, and some pages may be improperly drawn. To get an update, go to

Turning on font smoothing in Adobe Type Manager (ATM) can cause windows to come up blank. The workaround is to turn off the font smoothing option
in ATM. (Bug 58104)

If you have a dual-processor G4 running Mac OSX, Mozilla will stall. There are no problems with dual-processor G4's running MacOS 9. (Bug 71718)

In Mozilla Mail, the import utility only supports Eudora and text files.


Mozilla requires glibc 2.1 or later. (Bug 44787)

If you have Red Hat Linux 6.0, you can't launch Mozilla if Java 2 is installed. The problem doesn't occur with Red Hat 6.1 or higher. (Bug 58259)

For Red Hat Linux 7, you must install the Standard C++ libraries for Red Hat 6.x compatibility. Get the package from the Red Hat 7 installation CD or download it from Red Hat. (Bug 59012)


To install Mozilla on Solaris8 (64 bit), you must first install libstdc++. Download the Sun Netscape 6 install package and install libstdc++ from that package before installing or running Mozilla . (Bug 68604)


When using VTMW 5.4.5, transient windows must be decorated (not the default) for popup windows such as Find, Save and Preferences to function. (Bug 71920)

Installation Notes

Install into a new empty directory. Installing on top of previously installed builds may cause problems.

Windows Users: If you get the message, "uninstall.exe file is linked to missing export shell32.dll", delete %TEMP%\ns_temp.

If you are installing Mozilla on a multi-user operating system such as Linux, Unix, or Windows 2000, you should install it separately in the user directory of each user who plans to use Mozilla . (Bug 42184) If you install Mozilla in a shared write-protected directory, it may not run properly. (Bugs 42184)

When you install language packs and other .xpi files, downloading pauses until you click the browser's Stop button.

If you receive the message 'The program must close to allow a previous installation to complete' when launching, it means that file cleanup after an additional installation has not completed.

Suggested workarounds:

  1. In most cases, waiting a few additional seconds after the program exits will allow the cleanup process to complete and allow you to launch.
  2. Occasionally the installation process is waiting for another program to release a file the cleanup process needs. You may need to shut down other programs or reboot the computer to allow the installation process to complete.
  3. In rare cases, a file cannot be cleaned up correctly, so rename the file xpicleanup.dat file and retry the launch.
    Warning: Do not remove this file; its presence may indicate an incomplete. (Bug 84896)

Windows and Mac OS: It is strongly recommended that you exit all programs before running the setup program. Also, you should temporarily disable virus-detection software.

Mac OS: Mozilla will not run when the application is installed on a UFS partition. The workaround is to move the application folder to an HFS+ partition and it will
run correctly.

Mac OS: Mozilla installation requires some system extensions including QuickTime.

Mac OS: You should not restart your system with all extensions off before running Mozilla installation.


Windows and Linux: To run Java applets, you must install the Java Run Time Environment (JRE) plug-in. When using installer builds, everything should Just Work without any help.

See the Java section for more details about Java version compatibility.

Windows: If you're using the Installer build and you already have JRE 1.3.0_01 on your system Mozilla should recognize it. If it doesn't recognize it then follow the copy instructions for the zip builds.

If you're using the or builds After the JRE is installed on your machine, copy NPJava130_01.dll, NPJava130_01a.dll, NPJava130_01b.dll, NPJava130_01c.dll, and NPOJI600.dll from the install directory (something like C:\Program Files\JavaSoft\JRE\1.3.0_01\bin) to your Mozilla plugins directory (something like C:\Program Files\ Mozilla 0.9.3 \bin\plugins).

Linux With tar.gz builds on Linux, after the JRE has installed, put a symlink in your mozilla0.9.3 /plugins directory to the java2/plugin/i386/ns600/ directory.

With Linux RPM builds, you must install Java as the root user.

You may need to press the Stop button for the installation process to complete.

Redhat users who have problems with Java hanging should try setting the environment variable LD_ASSUME_KERNEL to "2.2.5". (Bug 80493)

Mac OS: You must have Mac OS Runtime for Java (MRJ) version 2.2 to run Java applets with Mozilla . If you have Mac OS version 8.5 through 8.6, you may need to upgrade your version of MRJ. For an upgrade, go to the Apple MRJ update download page.


Windows, Mac and Linux: Personal Security Manager (PSM) provides security (cryptographic) features for Mozilla .

Installing on Windows

Installing Java with low disk space may cause the Installer to hang. (Bug 45067) Before you begin installing Mozilla with Java, be sure to check your disk space (see System Requirements.)

To install Mozilla by downloading the Mozilla installer, follow these steps:

  1. Click the mozilla-win32-installer.exe link to download the file to your machine.
  2. Navigate to where you downloaded the file and double-click the Mozilla program icon on your machine to begin the Setup program.
  3. Follow the on-screen instructions in the setup program. The program starts automatically the first time.

To install Mozilla by downloading the .zip file and installing manually, follow these steps:

  1. Click the link or the link to download the .zip file to your machine.
  2. Navigate to where you downloaded the file and double-click the compressed file. Note: This step assumes you already have a recent version of WinZip installed, and that you know how to use it. If not, you can get WinZip and information about the program at
  3. Extract the .zip file to a directory such as C:/Program Files/ Mozilla 0.9.3 .
  4. To start Mozilla , navigate to the directory you extracted Mozilla to and double-click the Mozilla.exe icon.

Installing on Mac OS

Note: If the downloaded file does not expand automatically you must expand the file using a program such as StuffIt Expander. Expander ships with all new Macs and comes with the default system install, so you may want to do a find in Sherlock for "StuffIt" to make sure that you don't already have it installed.

You can get StuffIt Expander from Aladdin Systems.

If you do already have Expander, you need to set it to start by default. See the immediately preceding URL for info on using Expander.

To install Mozilla by downloading the Mozilla installer, (recommended) follow these steps:

  1. Click the MacMozillaInstaller.sea.bin link to download it to your machine. By default, the download file is downloaded to your desktop compressed in .bin format. A Mozilla Installer folder is created.
  2. Double-click the Mozilla Installer folder in the Finder.
  3. Double-click the Mozilla Installer icon.
  4. Follow the on-screen instructions to complete the installation process.
  5. To start Mozilla , open the folder where you installed Mozilla and double-click the Mozilla icon.

To install Mozilla by downloading the archive file and installing manually, follow these steps:

  1. Click the mozilla-mac-*.sea.bin link to download the Mozilla binary to your machine. By default, the download file is downloaded to your desktop compressed in .sit.bin format.
  2. Double-click the mozilla-mac-*.sea.sit.bin icon on your desktop.
  3. Choose the directory where you want to install Mozilla .
  4. To start Mozilla , open the folder where you installed Mozilla and double-click the Mozilla icon.

Installing on Linux

You must run Mozilla at least once to complete autoregistration and for the component.reg file to be written to the installation directory. If a different user (other than the person who installed the product) runs the program first, a core dump will occur. (Bug 49345)

Note: To run Java applets, you must install the Java Run Time Environment (JRE) v1.3 plug-in.

Note: These instructions use the bash shell. If you're not using bash, adjust the commands accordingly.

To install Mozilla by downloading the Mozilla installer, follow these steps:

  1. Create a directory named mozilla (mkdir mozilla0.9.3 ) and change to that directory (cd mozilla0.9.3 ).
  2. Click the link to download the installer file (called mozilla-i686-pc-linux-gnu-installer.tar.gz).
  3. Change to the mozilla directory (cd mozilla0.9.3 ) and decompress the archive with the following command:
    gunzip -dc moz*.tar.gz | tar -xvf -
    (This places the installer in a subdirectory of Mozilla named mozilla-installer.)
  4. Change to the mozilla-installer directory (cd mozilla-installer) and run the installer with the ./mozilla-installer command.
  5. Follow the instructions in the install wizard for installing Mozilla .

    Note: If you have a slower machine, be aware that the installation may take some time. In this case, the installation progress may appear to hang indefinitely, even though the installation is still in process.
  6. To start Mozilla , change to the directory where you installed it and run the ./mozilla command.

To install Mozilla by downloading the .tar.gz archive file:

  1. Create a directory named " mozilla0.9.3 " (mkdir mozilla0.9.3 ) and change to that directory (cd mozilla0.9.3 ).
  2. Click the link to download the non-installer mozilla*.tar.gz file into the mozilla0.9.3 directory.
  3. Change to the mozilla directory (cd mozilla0.9.3 ) and decompress the file with the following command:
    gunzip -dc moz*.tar.gz | tar -xvf - (This creates a "mozilla" subdirectory under your mozilla0.9.3 directory.)
  4. Change to the mozilla directory (cd mozilla).
  5. Run Mozilla with the ./mozilla run script.

To hook up Mozilla complete with icon to the GNOME Panel, follow these steps:

  1. Click the GNOME Main Menu button, open the Panel menu, and then open the Add to Panel submenu and choose Launcher.
  2. Right-click the icon for Mozilla on the Panel and enter the following command:


    where directory_name is the name of the directory you downloaded Mozilla to. For example, the default directory that Mozilla suggests is /usr/local/mozilla.
  3. Type in a name for the icon, and type in a comment if you wish.
  4. Click the icon button and type in the following as the icon's location:


    where directory_name is the directory where you installed Mozilla . For example, the default directory is /usr/local/mozilla/icons/mozicon50.xpm.

Installing RPM builds: The Red Hat RPM builds are created to work with the default Red Hat 6.x and Red Hat 7.x installations. Using these RPMs on Suse requires installation of the gdk-pixbuf package. (Bug 85218)

Uninstalling Mozilla


  • Remove the mozilla0.9.3 directory where you installed Mozilla

  • Remove the ~/.mozilla directory, which contains profile information


  • Go to Settings/Control Panel/Add Remove Programs and choose Mozilla 0.9.3

Mac OS

  • Remove the folder Mozilla from the Documents folder
  • Remove the file "Mozilla Registry" from the System Folder | Preferences folder
  • Remove the file "Mozilla Versions" from the System Folder | Preferences folder
  • Remove the folder where you installed Mozilla

Files Created or Used

prefs.js (Preferences file)
cache/ (cache directory)
newcache/ (Additional cache files)
cookies.txt (cookies file)
*cookperm.txt (used to selectively accept/reject cookies)
FieldSchema.tbl (files for auto form filling)
SchemaConcat.tbl (files for auto form filling)
SchemaValue.tbl (files for auto form filling)
URLFieldSchema.tbl (files for auto form filling)
signons.tbl and signonsx.tbl (logins and passwords file store)

mozregistry.dat ( Mozilla registry)

mozver.dat (stores version of Mozilla components) MozillaUninstall.exe ( Mozilla Uninstaller) Application Data\Mozilla ( Mozilla data directory on Win98) Mozilla Mozilla data directory on Win95
prefs.js in ~/.mozilla/[profile] (preferences file)
Cache in ~/.mozilla/[profile](cache directory)
newcache in ~/.mozilla/[profile](additional cache directory)
cookies (cookies file)
*cookperm (used to selectively accept/reject cookies)
FieldSchema.tbl (files for auto form filling)
SchemaConcat.tbl (files for auto form filling)
SchemaValue.tbl (files for auto form filling)
URLFieldSchema.tbl (files for auto form filling)
signons and signonsx (logins and passwords file store)

registry ( Mozilla Registry)

prefs.js (preferences file (use))
Cache (cache directory)
newcache (additional cache directory)
cookies.txt (cookies file)
*cookperm (used to selectively accept/reject cookies)

FieldSchema.tbl (files for auto form filling)
SchemaConcat.tbl (files for auto form filling)
SchemaValue.tbl (files for auto form filling)
URLFieldSchema.tbl (files for auto form filling)

Mozilla Registry

*Note: "cookperm.txt" ("cookperm" on Unix) is a file used to selectively accept cookies from certain sites and not from others. It is used only if you set your preferences so that you see a warning before accepting cookies. To do that: hand edit the prefs.js file to include:

  • user.pref ("network.cookie.rememberAboutCookies", true);

Known Problems


If you collapse the Navigation toolbar and close the browser window, the next time you start the browser the toolbar will not be visible. To restore the toolbar you will have to open a new window. Make sure that new window is the last window you close and the toolbar will be fine on the next start. (Bug 73064)

Mac OS: There is a known incompatibility between Mozilla and WebFree, a Control Panel commonly used to block HTML-based ads. When using Mozilla, disable WebFree. (Bug 13982)

Linux: Printing crashes with RedHat Linux if you don't have a printer name lp configured. Workarounds: 1) Configure the printer named lp (which is by default the printer name assigned on Redhat Linux). 2) Use a printer that is configured, e.g., lp0, by changing the print command in the print dialog so that it reads lpr -P lp0 (replace lp0 with the name of your printer). To see the list of configured printers, you can log in as root and use the following command: 'lpc status'. Alternately, you can use the RedHat 'printtool' application to graphically view and configure the printers on your system. (Bugs 78948, 92344)

Keyboard and Mouse

Double right-clicking on a page can disable the keyboard. (Bugs 30841 and 70812)

Linux: Keyboard shortcuts on Linux now use Ctrl instead of Alt as the modifier key, while Alt is used for menu shortcuts. If you wish to modify these shortcut keys, edit your prefs.js file as follows:

user_pref("ui.key.accelKey", 18);
(This changes the accelerator key from Ctrl (17) to Alt (18).)

user_pref("ui.key.menuAccessKey", 0);
(This changes the menu access key from Alt (18) to none.)

Event Handling

Wrong events are fired on FILE element. (Bug 4033)

Mouse wheel scrolling

Linux: You must have your X server properly configured to enable mousewheel scrolling. For XFree86, add a line to the Pointer section of your XF86Config files such as "ZAxisMapping 4 5". Also be sure that the Protocol line is set up correctly for your mouse.

Windows: Mousewheel scrolling does not work with all drivers. If you have problems, try updating your driver or disabling any "helper" programs that your mouse uses.

Mac OS: Mousewheel scrolling does not work with all drivers. If you have problems, try updating your driver or disabling any "helper" programs that your mouse uses.

(Mac OS 9.x ) Scroll wheel support for Kensington input devices requires Kensington MouseWorks 5.7 or higher. Version 5.7 is not yet shipping as of this writing; please check the Kensington website at for updates.

Dialog Boxes and Windows

If Mozilla is locked up but doesn't seem to have crashed, make sure there are no dialog boxes still open. Close each window on your desktop one at a time and if you uncover a dialog window, dismiss it. If you have multiple desktops, repeat these steps for each desktop.

This problem may affect Linux users downloading plugins. Follow these steps to resolve the problem:

  1. Minimize the plugin download window.
  2. Click "Cancel" to dismiss the dialog box.
  3. Re-open the download window and continue downloading the plugin.

Form Manager

Form Manager is not fully implemented in the Japanese version of Mozilla .


Many Linux systems (in particular, Red Hat Linux systems) have bad Arial fonts. (Bug 46415) If many Web pages, especially those using the Arial font, look unclear, small, or hard to read, the following links explain two ways you can change your font server to get better Arial fonts:

If that doesn't work, you may be able to fix the problem by renaming or removing /usr/share/fonts/ISO8859-2. For instance, enter the following command:

mv /usr/share/fonts/ISO8859-2 /usr/share/fonts.ISO8859-2

and then log out of Linux and log back in again. You can always undo this, if necessary, by entering the following command:

mv /usr/share/fonts.ISO8859-2 /usr/share/fonts/ISO8859-2


Mozilla needs to be configured to work properly with proxies such as Junkbuster that do not support the most recent HTTP specification. By default, Mozilla tries to use HTTP 1.1. To use Mozilla with a proxy that only supports HTTP 1.0, edit the HTTP Version from 1.1 to 1.0 in Edit | Preferences | Debug | Networking. (Bug 38488)

Setting Profiles

If you have a single profile from Communicator version 4.5 or later, that profile is automatically copied and converted for use with Mozilla . Profiles from earlier Netscape versions cannot be converted.

If you have multiple profiles to copy and convert, the profile manager dialog box appears. Click the profile you want to use and then click Start.

If problems occur during installation and your Communicator profile was not copied and converted, you can still use your profile. Launch Mozilla from the command line, adding the "-installer" option (that is, type "mozilla.exe-installer" on the command line) , or re-install Mozilla to see the profile manager dialog again.


Additional Internet Search Engines can be obtained at

The "View Frame Source" feature is not available from the View menu; however, it is available in the context menu. To see the context menu, click the left mouse button to put the mouse pointer in the frame and then click the right mouse button (Control-click on the Mac OS). (Bug 47139)

Several features of Page Information are not yet available, including: the File MIME Type, Source, Local cache file, Content length, Expires, Charset, and Security. Also, you cannot view information on frames, XML pages, or FTP pages. (Bug 52730)

Pages that appear to be rendered incorrectly may be due to standards compliance issues. See the Netscape Evangelism site for more details.

For this release, Send Page will be disabled for pages containing post data which cannot be cached. (Bug 91342)

The "Copy Link Location" context menu item does not work for links inside image maps. (Bug 78021)

Windowless plugins don't get some events. (Bug 90574)

XSLT support still has bugs. (Bugs 73936, 53030)


Plugins do not print in this release. (Bug 27478)

Printing web pages may not printout all pages due to table pagination problems. (Bugs 79834, 66804, 64447, 86921, 87374, 83683)

Problems printing pages with frames; not all pages may be printed. (Bug 84149)

Transparent backgrounds are printed as black. (Bug 12037)

Tables don't print when between pages or more than one page. (Bug 90732)

Mac and Linux: Cannot print landscape mode on Mac and Linux (Bug 24847)

Printing may be cut off at the right end. (Bug 84223)

Printing newsgroup messages with images leads to a crash. (Bug 92659)

Accessing Pages

Mozilla may not be able to connect to some secure (https) IBM Web servers. This is a problem with the servers' software, not with Mozilla . (Bug 54031)

If you use "Last page visited" as your Home (starting) page, if the last page you viewed had frames, it may not be displayed correctly when you next restart Mozilla . (Bug 58613)

You can't use arrow keys or edit commands in the URL bar if the URL bar received focus when the browser window was created. (Bug 83919)

Clicking on the Search button the first time reverts your preferences to the preset Mozilla search engine. This does not happen after you set the Default Search Engine preference again. (Bug 82401)

Mozilla only supports the use of SOCKS proxies for http and https connections. (Bug 89500)

Windows: Double browser window appears when opening an html or image document from the Windows environment. (Bug 59078)

Linux: You can't view hidden files or directories (such as .mozilla) using Mozilla .

Linux: Flash may crash with exported X display. (Bug 58937)

Linux: On Linux, there may be problems with ESD Audio and Flash. (Bugs 85772, 58339)

Downloading Files

Hourglass cursor, progress meter, and throbber do not stop spinning although downloading has been finished. Status bar says "Transferring data from ..." when page is done loading. (Bug 39310)


If the bookmark item in the sidebar doesn't work, remove the bookmarks tab from the sidebar and then re-add it. Click on the "Tabs" button in the Sidebar and select the Customize My Sidebar menu item. In the resulting dialog, remove the bookmarks tab, hit OK and restart Mozilla . Go back to the Customize window and add the bookmarks tab. (Bug 71685)

Bookmarks cannot be rearranged if you have sorted them. To rearrange them, select Unsorted from the View menu, or click the Name column header until the arrow disappears. (Bug 64768)

View Source

To view frame source, point to the frame and click the right mouse button (Control-click on Mac OS) and then choose View Frame Source from the context menu. (Bug 47319)

Page content generated by an online form isn't correctly reflected in the view source window.

Mac OS: The horizontal scrollbar in the View Source window might be missing. Resize the window to see the scrollbar. (Bug 56488)

Mail and News

In the Mail/News Account Settings: Server Settings dialog box, any changes you make to local directory settings won't take effect until you exit and re-start Mozilla . (Bug 2654)

Undo/Redo and Stop may not always work as expected. (Bugs 32178, 27468, 28129, 32035, and others)

Delete Message doesn't always work when you're using Next Unread Message. (Bug 44572) Try clicking the message again to enable Delete.

Biff works only on the first account and does not work for any other accounts in the same profile. Work around: select each account's inbox once and click on Get message. (Bug 85227)

'Get All New Nessages' checks for the default for the selected account only, with or without passwords saved. Workaround: Select each account's Inbox and click on Get Message the first time for that session. Get All New messages should work. (Bug 80296)

Mozilla does not warn the user of a low disk space condition. (Bugs 57902, 32443, 56565) Some symptoms you may see are:

  • Send Page fails to send the intended page attachment.
  • Copying a message to your Sent folder fails
  • IMAP: Status text indicates there are new messages to retrieve, but no new messages appear in the Inbox. Quit Mozilla , free some disk space, re-start Mozilla , and try again.
  • POP: You see an "unknown error" when trying to select messages that could not be downloaded. Quit Mozilla , free some disk space, re-start Mozilla , and try again. This workaround succeeds only if "Leave messages on Server" is enabled in the Mail/News Account Settings: Server Settings dialog box. (It must be enabled prior to the failed download.) If that option was not enabled, those messages are lost.

Mail account identity is not stored along with an unsent message. (Bug 59548)

Linux: You may encounter problems if you install Mozilla in a root user environment then run as another user. Problems include saving to Sent folder, Drafts, Templates or general authentication problems. (Bug 49397)

AOL Mail and Netscape WebMail Accounts

Mozilla does not support AOL Mail and Netscape WebMail, as Netscape 6 does. If you share your Netscape 6 profile with Mozilla, you may be able to see headers for messages in the account's Inbox if you have previously checked one of these accounts in Netscape 6, but you will be unable to interact with the messages. To access your AOL Mail, WebMail, or Netscape Instant Messenger, you need to use Netscape 6.

Receiving and Reading Messages

Not all of the choices offered in the Search Messages window are implemented or valid for certain mail folder or newsgroup selections. (Bug 40380)

You may not see the message header (From, Subject, Date, To, Cc, and so forth) when you read messages. This problem often occurs when you switch mail folders or newsgroups. To see headers, resize the window or the message content pane. (Bug 39655)


Don't try to download multiple attachments simultaneously. Download them one at a time. (Bug 49180)

In some cases you can't view more than one HTML/Web page attachment to a message in the mail window. The attachments will not all be shown or you may experience a crash when attempting to display them. (Bug 38398)

A crash may occur if you try to open or save a message attachment of a content type unknown to Mozilla . (Bug 44762)

Double-clicking on a JPEG file attachment will lead to a hang. (Bug 92367)

Composing Messages

You can't forward a message that has a signature file containing the HTML tag <div class="signature">. (Bug 49484)

Address Book

To import Outlook address books for Outlook to be imported, you must have the default mail client set to "Microsoft Outlook" in the Microsoft Internet Explorer. Then do this:

1. Launch Internet Explorer.
2. Click Tools in menu bar, then click Internet Options. The Internet Options dialog box appears.
3. Click the Programs tab and select "Microsoft Outlook" as the default e-mail client.
4. Hit OK and exit Explorer. (Bug 90206)

(Windows) You may need to try more then once before Outlook Express address books are imported successfully. (Bug 90206)

In Address Book, using "Select All" and "Delete" more than 500 cards may crash application. (Bug 90378)

Copying a large number of addresses between address books may cause crash. (Bug 82991)


If you have multiple filters configured for a mail account, incoming messages will continue to be evaluated against each filter (in the order listed in the Message Filters dialog) until a filter action of Move to Folder or Delete is executed. This differs from Communicator 4.x where any filter action would stop further filtering on a message. (Bug 30081)

Pop and IMAP

user_pref ("mail.allow_at_sign_in_user_name", true); will allow you to enter a username when you login to use mail. Add this string to your prefs.js file in your profile.

Note: Your prefs.js file is located in the Users50 directory on Windows and Mac OS, and in the .mozilla directory on Linux.

You must exit and restart Mozilla to see the effect of a change to the option: "show All IMAP mail folders" or "show only subscribed IMAP mail folders." To access this option: click the Advanced button in the Server section of the Account Settings dialog box. (Bug 38943)

When sending email from Cyrus IMAP mail accounts, you will get "The current command did not succeed. The mail server responded: Permission denied". Workaround: Redefine the special folder (sent, draft, template) under the Inbox folder. (Bug 91398)

If you delete marked messages immediately when Mail launches for the first time in "Mark as deleted" mode, you will not be able to recover them unless you use "Undo" immediately. (Bug 69151)


The Subscribe dialog box may not work with news servers that require authentication. If you open a password-protected newsgroup you may be prompted more than once for the user name and password combination.


LDAP directory entries that have ","s in their CNs (e.g. "Doe, John") may not be correctly quoted. (Bug 89198)

Offline Mail

Saving as a template from an IMAP account doesn't work offline. (Bugs 81690)

Saving a downloaded file (text, html, eml, template) while in offline mode does not work. (Bug 81690)

Saving a message while composing (Copies and Folder preferences) does not work properly. (Bug 64417)

Some mail items (offline and disk preferences, offline item selection, online/offline indicators in search/history/subscribe) do not display properly. (Bug 79801, 80970, 83555)

If using a theme other then the Modern theme, downloaded messages headers are displayed in italics. (Bug 86460)

New newsgroups can not be downloaded unless you have previously open the newsgroups and retrieved headers first. (Bug 84061)

For both Mail and Newsgroups accounts, the Disk Space UI preference: "Do not download messages locally that are larger than X kb" can't be set/changed. As a result it prevents you from downloading messages that are > 50kb. The only way you can download messages greater than that is to select the message and do a "Get selected Messages". Workaround: For messages > 50kb, select the message and use Get Selected Messages (File|Offline|Get Selected Messages) (Bug 86014)

Can't download messages approx. > 1Mb in size with Get Selected Messages or Get Flagged Messages. (Bug 91679)

In News, The preference 'Remove message bodies older than x days' can't be checked. (Bug 91560)

Moving/Copying a downloaded message (while offline) will result in not being able to read the message at the new folder while you are offline. Workaround: Go online to read it, then redownload the message to have it accessible when you are offline. (Bug 78809)

Can't 'Save a draft' or 'Save a Unsent Message' to a online folder. Workaround: To 'Save a Draft' or store an 'Unsent Message' use the default folders [Drafts or Unsent Messages] which are located under "Local Folders" as this works. (Bugs 64417, 83540, 83682)

If online and you are using Filters to sort your mail, then while trying to do a "Download and Sync" the result could be problems getting the messages to their appropriate folders. Workaround: If the user has been offline and when they go back online, click the "Get Msg" button on the toolbar to get messages to their appropriate folders instead of using Download and Sync. (Bug 87531)

If the user starts Netscape in offline mode (clicking the work offline checkbox in the profile manager), then tries to reply to a message while in offline mode, or double clicks on a message (which brings it up in a separate window), in some instances the application might crash. (Bugs 87923, 92368)

Using Download and Sync on numerous newsgroups might result in not getting all the messages downloaded the first time. Workaround: Use 'Download and Sync' on one or only a few newsgroups at a time, then uncheck them once synching is complete and select another couple of newsgroups and repeat the steps. Or go online and select the Newsgroup you want to download messages from and right click and do a "Get Messages for Account" or click "Get Mesg" on the toolbar. (Bug 87018)



ChatZilla is not finished, but is usable if you're willing to accept a subset of the commands offered in more mature IRC clients. A large percentage of ChatZilla users experience crashes, odd behavior, rash, shortness of breath, and an urge to fix bugs. If you would like to contribute, please tell us in the netscape.public.mozilla.rt-messaging newsgroup, or send an e-mail to

If you are not familiar with IRC, please check out the FAQs available at

Running ChatZilla

Start Mozilla with the -chat option to start ChatZilla, or select it from the Tasks menu.

More Info About ChatZilla

See the ChatZilla User's Guide for information on using ChatZilla. For info on building ChatZilla, click here. (Note that ChatZilla builds automatically on Windows and Mac OS).


You may not be able to simultaneously edit a document using both Composer and another editor. (Bug 37089)

You can't apply a font style across paragraphs and images. Font changes must be done within each paragraph.

Applying a font style across several words yields multiple font tags in the HTML code.

When the background color on a page is set, only the frames behind the lines of selected text are colored. Resizing the window triggers the proper repaint.

After applying a color to text, the text may appear partially highlighted.

Certain pages (such as ones that set frames) can't be edited. However, you are still able to choose the Edit Page option in the File menu for such pages. An editor window opens, but you are unable to edit the page.

Edit|PasteAs function is not functioning. (Bugs 73286, 41547)

File|Open Web Location, selecting to render in Composer does not open document in Composer. (Bug 71426)

When saving remote files, associated images are not saved. (Bugs 36419, 51746)

Switching between Normal and HTML Source mode inserts break (br) elements. (Bug 46227)

You can not print HTML Source. (Bug 82239)

Numerous shortcut keys do not function properly. (Bugs 26264, 43433, 48951, 57805, 61355, 70630, 57967, 58332, 58712, 26269, 53505, 76925, 80384, 60459, 57700, 67142, 4302, 69740, 48375)

Hourglass does not show when application is busy. (Bug 83300)

Broken image icon does not display in the application. (Bug 58646)

Some element icons do not render in Show All Tags mode. (Bugs 82465, 82459)

List editing can cause nested lists to outdent to next level list. (Bug 52675)

Remove option from personal spell check dictionary does not work. (Bug 43348)

A blank window opens when clicking on the Browse button the 2nd time. Workaround: After editing the page more, if you want to view the new changes in Browser, first save the Composer file, go to the Browser window loaded before, and click the "Reload" button (or use "View | Reload" menu command). (Bug 59497)


TLS support: The Secure Sockets Layer (SSL) protocol defines rules governing authentication between a web site and browser software and the encryption of information that flows between them. The Transport Layer Security (TLS) protocol is an IETF standard based on SSL. TLS 1.0 can be thought of as SSL 3.1. [Mozilla/Netscape 6.1] supports both SSL and TLS.

Some servers that do not implement SSL correctly cannot negotiate the SSL handshake with client software that supports TLS. Such servers are known as "TLS intolerant."

When you select the "Enable TLS" option in the SSL preferences panel, the browser will attempt to use the TLS protocol when making secure connections with a server. If that connection fails because the server is TLS intolerant, the browser will fall back to using SSL 3.0--with one important exception: If you are using a proxy for SSL connections, the browser will not attempt to use TLS at all. Instead, it will attempt to use SSL 3.0. (Bug 88244)

Certificate Manager sometimes slow to open. If you have many personal certificates listed in the Certificate Manager, it can take thirty seconds or more to open. This problem is exacerbated if you have selected the option "Use OCSP to validate all certificates using this URL and signer" in the Validation preferences panel. Turning off this option improves opening time. (Bugs 82212 and 87654)

Certificate Manager may crash if you select fields in the Details tab of the Certificate Details window. The workaround is not to select anything in the Details tab. (Bug 90962)

Incorrect computer clock time can cause new certificates to be temporarily invalid. If your computer's clock is not set correctly, attempting to use a new certificate immediately after receiving it may result in a "not yet valid" error. If you reset your computer clock to the correct time, the problem will disappear. (Bug 90639)

Generating a key while obtaining a new certificate can take a long time. No feedback is provided while a new key is being generated, which can take a long time for long keys or dual keys. As a result, it may appear that your computer temporarily hangs while you are obtaining a new certificate. (Bug 79153)

Restoring a certificate to a smart card can take a long time. No feedback is provided while restoring a certificate to a smart card, which can take a long time since smart cards are relatively slow devices. As a result, it may appear that the restoration is not happening. (Bug 52321)

Under rare circumstances, Netscape 6.1 may crash if certain security warnings are turned on. These preferences are found under Edit, Preferences, Privacy and Security, SSL. Turning off the "Entering a site that supports encryption" and "Entering a site that uses low-grade encryption" warnings ahead of time is a workaround to preventing a crash. (Bug 88120)


If you are using the Classic theme, some preference panels may be displayed incorrectly or may have missing elements. If you view a different preference panel and then return to the one you're working in, the display is corrected. (Bug 51241)

Preferences window initial size doesn't always give hints on all options available. Resize the window from its lower right corner to see them all. (Bug 53375)


Plugins installed for Communicator 4.x may not be available for Mozilla . Workaround: install these plugins in the Mozilla Plugins folder.

Microsoft Media Player file embedded in web pages may not work. (Bug 66015)

Macintosh: Mozilla now scans for plugins in the system's "Internet Plugins Folder" first.

Macintosh: Users will see the browser context menu pop up after dismissing a plugins context menu on Mac. Workaround: To remove the unwanted browser context menu, click inside the plugin area with the mouse once. (Bug 75456)


Mozilla has been tested with all 1.3.0_* versions of the JRE, and JRE 1.3.1, and beta versions of JDK 1.4. J2SE releases previous to 1.3.0_01 will not work with Mozilla .

LiveConnect does work with Mozilla 0.9.3 . There remain some LiveConnect problems with the combination of Mozilla 0.9.3 . and JDK/JRE 1.3.X. Fixes for a number of remaining LiveConnect problems are being incorporated into JDK 1.4 and will be available when that release of JDK/JRE is available later this year.

Running J2SE in 256-color mode may cause a flicking problem.

Linux: LiveConnect support now works if you use Mozilla 0.9.3 with JRE 1.3.1. Additional LiveConnect problems are being addressed in JDK 1.4 as mentioned above.

If Java doesn't work, make sure the following is true:
On Windows:
Copy the NPOJI600.DLL from C:\JDK*\jre\bin to "\plugins" directory of your installation.
On Unix:
Make a soft link from /plugins/ to /usr/java/j*/jre/plugins/i386/ns600/


On OS X, there is no "Default Downloader Plugin" (aka. the Default Plugin) and Java is not working yet. (Bug 88870)

Using spell check in OS X will may lead to a crash (Bug 91000)

International Release Notes


Mozilla has been designed to display many different languages without extra steps. The user should be able to browse and use e-mail without complicated setups or efforts when necessary fonts are available on the system.

Mozilla can be used with more than one language pack, which lets the user change the menu language and relevant URLs.

Bi-directional text support enabled for Hebrew and Arabic thanks to the contribution by IBM. Arabic shaping currently works only on Windows platforms which have full Arabic support installed. Arabic support is available for Win 2000 by installing an Arabic locale from the install CD. Other Windows platforms may not provide full Arabic support except under Middle Eastern enabled or localized versions. Arabic shaping is not currently available on Macintosh, Linux or other platforms. (Bug 82383)

Sidebar tabs and bookmarks will not change when you choose another region. (Bug 87939)

Language/Region Packs downloaded in 6.0x appear in View menu after upgrade but do not function. A user that wants to continue to use locale packs that were downloaded in 6.0x should keep 6.0x by installing 6.1 in a new folder. The old content packs will not appear in the 6.1 View menu, but will still be available for use in 6.0x. Any profile set to a non-default locale in 6.0x will revert to the default locale in 6.1. To use locale packs in 6.1, it is necessary to download new locale packs via the View menu (View>Set Language/Region>Download More) or via Preferences (Edit>Preferences, expand Appearance category, select Content Packs panel, then click Download More on lower-right). (Bug 91721)

If you are using Chinese, Korean or Japanese language Windows 9x/ME and are having a non-start or crash problem when trying to start up Mozilla , read the Java section of the Known issues section below.

You may be unable to print out Japanese characters from Win98-J with HP Laser Jet driver (Japanese version). Workaround: Install the driver that comes with the Japanese Windows 98 installation CD. (Bug 86989)

General and Profile Manager

Windows NT/2000: If you create a non-ASCII user name (e.g. Japanese) and if it does not have the Power user or Administrator status, a new profile creation may fail. In such a case, instead of accepting the default location for profiles, choose an alternate location whose path name does not contain non-ASCII characters.

A path name that contains non-Latin 1 characters is not saved correctly. Initially they look OK but when saved, they turn into unreadable characters. A file that is defined using such characters may not be found, e.g. a mail signature file. A workaround is to use only ASCII characters for file and path names.

Profile migration does not work correctly if Communicator 4.x profile names contain 2-byte characters (e.g. Japanese) with 0x5C byte Shift_JIS character.

Shift_JIS Full-width tilde character (0x8160) and a few other Japanese symbol characters have differing correspondences to Unicode mapping tables depending on platforms. This causes characters like these to display incorrectly in some situations on Macintosh.

Linux: When migrating profiles created by Communicator 4.x under Japanese EUC locale, Address Book entries may not transfer correctly. Workaround: You can edit preferences.js file and change the charset name "euc-jp" (lowercase) to "EUC-JP" (uppercase) for lines containing an entry like the following: "user_pref("ldap_2.servers.pab.csid", "euc-jp");"

Linux: Under a Japanese locale, the window title in Japanese (reflecting the title of a Web page) may not show correctly if the Web page does not match the charset of the Japanese locale, e.g. Shift_JIS title on an EUC locale.

Linux: On Red Hat Linux 6.0 Japanese, the license agreement for the Japanese installer may display empty. Workaround: Click OK and move on to the next step. This problem does not occur on RH 6.1 and later.

Navigator and Composer

Mozilla does not support Dynamic Fonts. (Note: It was supported in Communicator 4.x.)

Files and directories on a local disk bearing non-Latin 1 names may not be accessed by inputting the names into the Navigator location field.

The charset attribute within a SCRIPT tag, i.e. for JavaScript, does not work. Instead JavaScript uses the charset of the document.

With the Windows 2000 IME, most of the new IME features (e.g. reconversion) are supported but some features may not work correctly.

Mac OS: Non-ASCII non-Latin 1 info stored in Internet Config will not show correctly in auto-fill fields such as "Your name" field in the Mail account setup dialog. If this happens, you can manually correct auto-filled entries.

Mac OS: The Japanese language pack or Japanese release can be used on an English Mac OS if the Japanese Language Kit has been installed on the Mac OS. (The Japanese Language support comes free with Mac OS 8.5 or later as an optional install item.) The menu and dialogs, however, will not show as Japanese unless the " Mozilla " program is registered as a Japanese language program. To do this, use the (Japanese) Language register program found in the "Apple Extras" directory.

Mac OS: The Character Coding menu check mark does not get updated promptly and shows incorrect indication of the current page encoding.


POP and Local message body search does not work with non-Latin 1 key words.

Filtering by body key has not been implemented.

The "Edit as New" menu does not correctly quote the original non-ASCII text body if the original message does not contain MIME charset information.

When you quote the original message in reply, sometimes you see the quoted text as corrupted and unreadable. If this problem occurs, check that you don't have multiple Mail folder windows open. When multiple mail folders/windows are open, the reply charset reflects the charset of the selected message in the last window opened rather than the current message from which the reply message is created. Workaround: The user can either close all Mail folder windows except the current one, or select a message in the last window opened which bears the same charset as the one that is being quoted in reply.

Character Coding menu is not effective in a standalone message view window. The standalone window also does not inherit the encoding of the Mail view window if the original message contains no MIME charset or incorrect charset information. The latter two can be overridden but its effect is not inherited into the standalone window.

Japanese Auto-detection may fail sometimes with EUC-xx and UTF-8 attachments, which lack MIME charset information.

The Character Coding menu cannot correct the thread pane display of non-MIME encoded headers. If the message displayed lacks MIME charset information, the thread pane display obeys the default message display charset set in the Preferences dialog box under "Mail & Newsgroups | Message Display | Languages". Correctly setting this option to the charset most often used in the user's mail viewing helps avoid display problem of this type.

Mac OS and Linux: View Page Source does not work for viewing a message source when the Auto-Detect (All) is on. To use this function in Mail, turn off the Auto-Detect (All) from the Character Coding submenu of the View menu.


You may see an extraneous vertical bar or a question mark in the window title display of a header subject line. This is a misinterpreted Tab character sent from an IMAP server as part of a line folding sequence. This problem does not occur under a POP mail account.

You may get an error message saying that a mailbox does not exist when you attempt to "Empty Trash". This problem is caused when the Trash folder contains folders bearing non-ASCII names. You may not see them with Mozilla but you can delete them using Communicator 4.x. This will eliminate the warning dialog.


Some cases have been reported in which Windows 9x/ME Japanese users have a problem starting Mozilla when there is a prior installation of older JDK or JRE under the operating system in use. The JRE 130_01 that ships with Mozilla contains many fixes since the official release of JRE 1.3. If you are using an older version of JRE 1.3 or the US version of JRE 1.3 under Japanese Windows, you may experience this non-start problem.

To determine if the non-starting problem is due to Java installation, follow these steps:

    1. Locate the Plugins directory (which is found in the same directory as the Mozilla executable).
    2. Remove all the Java plugin files from the Plugins directory, i.e. the files whose names begin with "npjava...". Remove also the NPOJI600.dll file if you find one. Back them up in another directory so that you can restore them later.
    3. Restart Mozilla . If Mozilla starts, then you have a Java related non-start problem.

If you have the Java problem as described above or want to install updated JRE 130_01 shipped with Mozilla , follow these steps (Note: This type of problem has not been reported for Windows NT4/2000, but if you experience this problem on the latter two platforms, follow these steps for those platforms also):

    1. Click the Start button, open the Settings menu, and choose Control Panel.
    2. Double-click the Add/Remove Programs icon and select the Install/Uninstall tab.
    3. Locate the old JRE installation (Java Runtime Environment) and delete it.
    4. Run the Mozilla installer and choose either "Complete" or "Custom" installation making sure that Java is installed in the latter option. (Note that the "Typical" install does not install the JRE package but if there is an existing JDK or JRE on the operating system, the installer copies Java plugin files and place them into Mozilla 's Plugins directory.) This will install the latest version of JRE 130_01, which works with Mozilla .

Mac OS and Linux: Display of non-ASCII characters (particularly Chinese/Korean/Japanese) in applets may not work without correct font settings in file.

Using the Quality Feedback Agent with Automatic Proxy Configuration

Windows: If you are using automatic proxy configuration, and you want to use the Full Circle Talkback Quality Feedback Agent to send incident reports to , you need to replace the talkback.ini file with one that contains the appropriate proxy configuration information. Follow these steps to do so:

  1. If you are using an HTTP proxy, or both an HTTP and SOCKS proxy, create a file named talkback.ini, containing the following three lines, using your proxy host name, domain, and port:
  2. UseUserHTTPProxyInfo=1

    where xxxx is your proxy port number.

    If you are using a SOCKS Proxy, create a file with these three lines:


    where xxxx is your SOCKS port number.

  3. Replace the existing talkback.ini file with the version you created.

On Windows 95 and Windows NT systems, copy the talkback.ini file to the following directory location within the directory that contains the Mozilla.exe file: \Fullsoft\data\talkback.ini

A Note For Web Developers

For a list of known issues with support for Web standards (HTML 4.01, CSS1/2, DOM1/ 2, XML, RDF), JavaScript, Java, and Plug-ins in Mozilla , see the following document, which may be updated from time to time:

How To Get Involved With Mozilla

  • Join us on Bug Day. If you want to help test Mozilla, but don't know where to start, join us on Tuesdays at 3:00PM PST on the #mozillazine IRC channel on There you can meet friendly Mozillans who can help you learn the process and get you started.
  • Join the BugAThon. If you can script, you can help simplify test cases.
  • To become even more involved, check out these suggested starting points.

Where To Find Other Builds

  • Download the latest major release of Mozilla from
  • Download today's build of Mozilla from the FTP site.
  • Learn how to build Mozilla yourself.