SeaMonkey Changelog

New in version 2.32

January 14th, 2015
  • The Spell Check dialog is now resizable.
  • Generational Garbage Collection has been enabled.
  • Improved handling of dynamic styling changes to increase responsiveness.
  • Implemented HTTP Public Key Pinning Extension (for enhanced authentication of encrypted connections).
  • Reduced resource usage for scaled images.
  • Fixed several stability issues.

New in version 2.30 (October 16th, 2014)

  • OMTC (Off Main Thread Compositing) has been enabled by default on Windows.
  • OpenH264 support (sandboxed) has been added.
  • A new CSP (Content Security Policy) backend was implemented.
  • Support for connecting to HTTP proxies over HTTPS was implemented.
  • Improved reliability of the session restoration.
  • WebCrypto support has been enhanced: Added RSA-OAEP, PBKDF2 and AES-KW support, implemented wrapKey and unwrapKey, enabled import/export of JWK-formatted keys.
  • Fixed several stability issues.

New in version 2.29 (September 8th, 2014)

  • URLs that are too long to be shown completely appear in a tooltip now when hovering the location bar.
  • Coloring of the location bar for HTTPS URLs can be disabled through Preferences now.
  • Certain search engines can be discovered automatically now.
  • The status bar padlock icon features a context menu now.
  • You can now insert formulas in Composer using a dialog (LaTeX to MathML).
  • Feed items can be tagged automatically according to feed category tags now.
  • Searching within a message compose window will now display the find toolbar.
  • The account name is now shown in the status bar when downloading messages from POP servers.
  • Localizability of custom reply headers has been improved (mailnews.reply_header_* preferences).
  • Contact autocompletion in message composition windows now searches for all terms separately (AND search).
  • You can now search for contacts containing parentheses.

New in version 2.26 (May 2nd, 2014)

  • The delimiter for forwarded messages can now be configured.
  • An option to not strip signatures on reply has been added to prevent top signatures from deleting the body.

New in version 2.25 (March 20th, 2014)

  • Newsgroup names can now be entered using autocompletion.
  • See the changes page for a more complete overview.

New in version 2.24 (February 6th, 2014)

  • The DoNotTrack and Prompt on Sanitize preferences are now kept in sync.
  • A pref (mailnews.p7m_external) has been added to allow users to choose an alternate application/pkcs7-mime handling.
  • Support for Atom Threading Extensions (RFC 4685) has been added.
  • Migrating profiles from Thunderbird supports the new signons file format now (support for the old format has been dropped).
  • Autocomplete drop-downs (e.g. used on the Location Bar and Open Location dialog) now show favicons for their entries.
  • The account name is now displayed in the status bar for all messages when checking mail.
  • IMAP alert messages now show the server of the corresponding mail account.
  • Newsgroup names are now searched for all search strings combined (AND-search) on the subscribe dialog.

New in version 2.23 (December 12th, 2013)

  • Download progress is now shown in the Mac OS X app dock icon.
  • EXIF orientation is now being used when displaying attached images in MailNews.
  • "This folder is being processed... to get messages." alerts on active MailNews folders now identify the account or folder.
  • MailNews notifications have a new look.

New in version 2.22 (November 18th, 2013)

  • Sorting messages by date can now be configured to look at the thread root instead of the newest message in it (pref: mailnews.sort_threads_by_root).
  • Plugins doorhangers now allow to activate different plugin types independently.
  • The proxy popup is now also available from the MailNews main window.
  • A new Recipients column has been added that shows all recipients (To, CC, BCC).
  • The default HTML5 audio/video player controls allow to change the playback rate now.
  • A "Validate this page" entry has been added to Tools/Web Development.
  • The Firefox devtools debugger can now be used to debug SeaMonkey remotely.

New in version 2.21 (September 18th, 2013)

  • Implemented an option to thread messages received by date.
  • Allowed deletion of news posts by default.
  • Implemented optional taskbar preview-per-tab.
  • Added support (permission prompt) for desktop notifications.
  • Added Isn't operator for searching by Priority.

New in version 2.20 Beta 3 (July 31st, 2013)

  • Some private windows appeared in the undo close window list (bug 887045).
  • The Private Browsing shortcut key has been changed as it conflicted with spellcheck (bug 891081).
  • Remote debugging did not work if any tabs had no title (bug 889352).
  • Clicking on new mail notifcation opened two MailNews windows when no MailNews window was open (bug 840474).

New in version 2.19 (July 3rd, 2013)

  • SeaMonkey-specific changes:
  • Mark -> As Read now checks the state of all selected messages instead of only the first one's.
  • Notifications for mixed content blocker have been implemented.
  • A new 3rd-party cookie restriction to visited websites option has been added to the Cookies pref pane.
  • The context menu Search option is now available for textareas and input fields.
  • Website storage mechanisms are now available in the Data Manager (localStorage, indexedDB, etc.).
  • "Open Containing Folder" is now already available during download.
  • See the changes page for minor changes.
  • Mozilla platform changes:
  • asm.js optimizations (OdinMonkey) have been enabled for major performance improvements.
  • Improved WebGL rendering performance through asynchronous canvas updates.
  • Plain text files displayed within the browser will now word-wrap.
  • For user security, the Components object is no longer accessible from web content.
  • Improved memory usage and display time when rendering images.
  • The Pointer Lock API can now be used outside of fullscreen.
  • CSS3 Flexbox has been implemented and enabled by default.
  • The new Web Notifications API has been implemented.
  • Added clipboardData API for JavaScript access to a user's clipboard.
  • Support for new HTML5 and elements has been added.
  • Fixed several stability issues.

New in version 2.19 Beta 2 (June 27th, 2013)

  • Mitigate clickjacking of about:certerror (bug 871536).
  • Workaround for unusually large DirectWrite font line heights (bug 868495).
  • Private downloads should ignore the Download Manager (bug 873355).
  • Private windows should not opt out of the private browsing session (bug 874042).
  • Private sidebar searches should not open in a normal window (bug 875889).
  • Last page visited should not include private browsing windows (bug 883577).

New in version 2.19 Beta 1 (June 24th, 2013)

  • The new mail alert has been disabled for now due to issues on Mac (Bug 840474).
  • The Geolocation prompt does not offer an action in Private Browsing mode anymore if the action remembers permission for more than a session (Bug 870728).
  • A slightly less useless access key has been chosen for the new Error Console Filter textbox label (Bug 860851).
  • Mixed content blocker preferences are now handled by Sync (Bug 860970).
  • LDAP passwords were requested for each lookup even if they were saved (Bug 833971).
  • Get New Messages for All Accounts has been fixed (Bug 855631).
  • The "File" button in the "Search messages" window has been renamed to "Move" (Bug 325777).
  • The entries in the "Trust junk mail headers set by" menu list are now sorted (Bug 847172).
  • The check for the allowed mail storage directory has been made more universal and accessible to extensions (Bug 848477).
  • A wrong message and reason was reported with untrusted CA roots when signing email (Bug 465351).
  • The IMAP-specific "Empty trash" confirmation dialog has been removed and the mailnews.*.dontAskAgain and mail.*.dontAskAgain prefs been merged (Bug 448624).
  • Help now explains what happens when Safe Browsing blocks a website (Bug 852809).
  • Email addresses with trailing whitespace could be displayed wrongly when composing and cause lost mails and malformed duplicate address book entries (Bug 286760).
  • Switching the account during message composing did not apply the signing prefs from the new account (Bug 624432).
  • The Help Glossary has been extended with new Privacy & Security terms (Bug 847182).
  • Growl support has been removed again (Bug 852461).
  • Safe Browsing debug has been turned off and Sync support turned on (Bug 851789).
  • The Bookmarks Toolbar was not populated with items if the grippy was collapsed when the browser window was opened (Bug 818437).
  • Special mail folder icons were not shown for IMAP shared folders (bug 840003).
  • Null bytes are now stripped from document titles when setting the window title in order to prevent Private Browsing spoofing (Bug 851527).
  • Invalid message ContentType values are handled better now (Bug 459474).
  • A tutorial section on User Tracking has been added to Help (Bug 844823).
  • The Customize Headers window prompted twice (Bug 524662).
  • ReplyTo has been added to the default IMAP headers in order to fix Reply with Template behavior (Bug 655428).
  • The offline folder flag will no longer be set for SPAM and TRASH folders (Bug 809990).
  • Help now includes documentation for the Offline Applications pref pane (Bug 771534).
  • The main Privacy & Security pref pane is now documented and features a Help button (Bug 631566).
  • The access key for "Perform these actions" now sets/moves focus to first action item in the Filter editor (Bug 825449).
  • Clear Private Data (preferences and menu) documentation has been added to Help (Bug 416234).
  • An "Error parsing template: expected to be first" message could appear when opening the virtual folder list dialog (Bug 747325).
  • The umask for emails saved as a file were not respecting the system umask (Bug 472865).

New in version 2.18 Beta 2 (April 22nd, 2013)

  • Some parts of click-to-play did not work if doorhangers were disabled (Bug 860537).
  • The Open Link in New Window context menu item had stopped working in MailNews (Bug 860905).
  • The browser feed preview had been broken due to Private Browsing changes (Bug 856322).
  • Per-site click-to-play permissions had stopped working (Bug 854867).
  • An LDAP password was requested for each lookup even if it was saved (Bug 833971).
  • Creating/amending mailing lists in the Address Book had been broken (Bug 859068).
  • The tabbed browser uses the favicon service in a privacy-aware way now (bug 856406).
  • The Open Location dialog does not save the state anymore when opened from a private window (bug 844497).
  • Private downloads did not update (bug 849440).
  • Save As from the context menu did not take the privacy status into account (bug 851304).
  • Added icons for security notifications (bug 853268).
  • Fixed the browser feed preview to work with XBL scopes (bug 846763).

New in version 2.17 (April 4th, 2013)

  • Continued performance improvements around common browser tasks (page loads, downloads, shutdown, etc.).
  • Continued implementation of draft ECMAScript 6 (clear() and Math.imul).
  • now supports blend modes.
  • Various and improvements have been implemented.
  • The Details button on the Crash Reporter has been fixed (bug 793972).
  • Fixed several stability issues.

New in version 2.16 (February 21st, 2013)

  • Reply to List is now supported.
  • SSL-related warning prompts (leaving or entering a secure site, viewing mixed content) have been replaced by less intrusive, non-modal notification bars.
  • See the changes page for minor changes.

New in version 2.15 (January 9th, 2013)

  • SeaMonkey-specific changes:
  • SeaMonkey can be set as default client/browser on Mac and Linux now.
  • See the changes page for minor changes.
  • Mozilla platform changes:
  • Preliminary support for WebRTC has been added.
  • Image quality has been improved through a new HTML scaling algorithm.
  • CSS3 Flexbox has been implemented.
  • Support for new DOM property window.devicePixelRatio has been added.
  • Support for @supports has been added (disabled for now).
  • Startup time has been improved through smart handling of signed extension certificates.
  • HTML5: Support for W3C touch events has been implemented, taking the place of MozTouch events
  • Insecure content loading has been disabled on HTTPS pages (see bug 62178).
  • Fixed several stability issues.

New in version 2.10 (June 7th, 2012)

  • SeaMonkey-specific changes:
  • The domain name is highlighted in the location bar by default now, configurable in Preferences.
  • The amount of tabs to be restored concurrently can be configured in Preferences now.
  • News username and password auth dialogs have been combined and show for which server the prompt is now.
  • Mozilla platform changes:
  • The new minimum supported Windows version is now XP SP2, Windows 2000 support has been dropped.
  • The SPDY protocol now enabled by default for faster browsing on supported sites
  • The column-fill CSS property has been implemented.
  • Experimental support for ECMAScript 6 Map and Set objects has been implemented.
  • Support for the CSS3 background-position property extended syntax has been added.
  • The :invalid pseudo-class can now be applied to the element.
  • The CSS turn unit is now supported.
  • Fixed several stability issues.

New in version 2.6 Beta 1 (November 28th, 2011)

  • Added Print Preview support to Composer
  • Added update channel indication to About SeaMonkey page (about:)
  • Mozilla platform changes:
  • Added Type Inference, significantly improving JavaScript performance
  • Added support for querying Do Not Track status via JavaScript
  • Added support for font-stretch
  • Improved support for text-overflow
  • Improved standards support for HTML5, MathML, and CSS
  • Fixed several stability issues

New in version 2.1 RC2 (June 7th, 2011)

  • Sync (f.k.a. Weave) is now included directly in SeaMonkey. Sync allows you to keep your browsing history, passwords, bookmarks, preferences and tabs in sync across different devices (computers) in a secure way.
  • SeaMonkey windows can now be themed with Personas (lightweight themes).
  • The bookmarks system has been reworked to use the Places framework shared with Firefox (already used for history data in SeaMonkey 2.0), including a new Bookmark Manager and fast bookmarking button in the location bar.
  • Find in Page now works with a toolbar instead of a modal window.
  • OpenSearch plugins are now supported and the default for web search.
  • An optional search bar (including suggestions if the search engine supports it) is available in browser toolbar customization, and an engine manager for OpenSearch is available.
  • More toolbar widgets are now customizable.
  • The new Add-ons Manager opens directly in the browser now and has received a major facelift.
  • The new Data Manager now unifies cookie, permission, password, and form data management.
  • Flash cookies (LSOs) will now be removed when using Clear Private Data / Cookies (requires Flash Player 10.3 or better).
  • Plugin crashes do not take down the whole application anymore since plugins run in their own processes now.
  • Plugins now work in feeds shown in MailNews windows.
  • The feed preview UI and the Helper Applications preferences can now detect the system's default feed reader and use it.
  • Page zoom is being remembered on a site-specific basis now.
  • The browser tab bar is now scrollable to cope with tab overflow. This includes an "All Tabs" navigation button to quickly list all open tabs.
  • You can now drag and drop downloads, e.g. from the Download Manager to the desktop.
  • SeaMonkey now shows "doorhangers" for notifications like remembering log-in passwords or after installing an extension.
  • The new DoNotTrack HTTP header is supported (configurable in Preferences).
  • A page with Troubleshooting Information (about:support) and the option to restart in Safe Mode are now available from the Help menu.
  • Loading the URL about:memory now shows how much memory is used by different parts of SeaMonkey.
  • SeaMonkey should now support more websites that previously appeared to only work with Firefox (configurable in Preferences).
  • Built-in extensions (ChatZilla, JavaScript Debugger and DOM Inspector) are now installed into the profile.
  • News messages can now be deleted from local storage.
  • Cascaded Session Restore improves restoring large browsing sessions.
  • SeaMonkey now uses Omnijar which results in fewer installed files, less fragmentation and better startup time.
  • Platform-specific changes:
  • On Linux, desktop notifications (e.g. mail alerts, finished downloads) show up in the native environment.
  • Mozilla platform changes:
  • Better performance on startup and shutdown, and memory usage improvements.
  • Protection from out-of-date plugins has been added.
  • Text areas in web forms are now resizable.
  • CSS :visited selectors have been changed to block ways that websites can quickly check a user's browsing history.
  • The WOFF format for downloadable website fonts is now supported.
  • SMIL animation in SVG is now supported.
  • New CSS attributes such as gradients, background sizing, and pointer events have been implemented.
  • A new HTML5 parser is used for all HTML documents.
  • New DOM and HTML5 features including the Drag & Drop API and the File API are now supported.
  • JS-ctypes support has been improved, allowing in-application JavaScript code to access native system libraries.
  • HTML5 video can now be viewed full screen and supports both the WebM format and the "buffered" property.
  • Web developers can animate content using CSS Transitions.
  • The W3C Indexed Database API is now available to websites.
  • JavaScript is faster than ever with the new J├ĄgerMonkey engine.
  • Support for WebGL, Direct2D and Direct3D acceleration on Windows has been added (see about:support for support and Preferences for configuration).
  • The HSTS security protocol and the proposed Audio Data API are available.
  • OpenType support has been improved.
  • HTML5 Forms API support has been added.

New in version 2.1 Beta 3 (April 8th, 2011)

  • When you start SeaMonkey in Safe Mode, you are now presented with a dialog that allows you to permanently apply some of the Safe Mode changes. Furthermore you can enter Safe Mode directly from the Help menu now.
  • If a plugins crashes, you are now presented with several options right there (e.g. reloading the page).
  • Built-in extensions (ChatZilla, JavaScript Debugger, DOM Inspector and DebugQA) are now installed into the profile.
  • SeaMonkey Sync supports the easy setup process (J-PAKE) now.
  • Windows 7 Jump Lists support was added.
  • Outdated plugins are detected now.
  • Tabs can now be switched using mouse scrolling (in addition to scrolling the tab bar).
  • WebGL support via ANGLE has been added.
  • An optional search bar (including suggestions if the search engine supports it) is available in browser toolbar customization, and an engine manager for OpenSearch is available.
  • The delete action in the MailNews Advanced Search dialog has been fixed.
  • Plugins now work in feeds shown in MailNews windows.
  • ChatZilla is working again.
  • The JavaScript Debugger Venkman is working again.
  • Download progress is now shown in the Windows 7 taskbar.
  • Cascaded Session Restore improves restoring large browsing sessions.

New in version 2.0.9 (October 20th, 2010)

  • Security fixes
  • Fixes for a number of non-security-relevant crashes, increasing the stability of the whole platform and the Mail & Newsgroups part of SeaMonkey

New in version 2.0.7 (September 8th, 2010)

  • Security fixes
  • Message-ID searches on Google Groups work again
  • Add-ons preferences button for Lightning should work now

New in version 2.1 Alpha 2 (July 8th, 2010)

  • New Add-ons manager (bug 561600)
  • Drag URL/file to/from SeaMonkey's Download Manager (copy/move to desktop/folder) (bug 192728)
  • Save multiple messages as individual files in directory (bug 555972)
  • Make Search, Folder Location and Views widgets for MailNews customizable toolbars (bug 521927)
  • WebM video is now supported for HTML5 tag. (bug 566245)
  • View source is now consistently taken from the platform and appearing in a SeaMonkey look and feel across all invocations. (bug 411754)
  • Loading the URL about:memory now shows how much memory is used by different parts of SeaMonkey.
  • SeaMonkey now supports a lot of the same tabbrowser API as Firefox. (bug 467867)
  • Search and Go buttons widgets for Browser are now customizable. (bug 529647)
  • The feed preview UI and the Helper Applications preferences can now detect the system's default feed reader and use it. (bug 471346)
  • HTML5 Websockets are now available to website authors. (bug 472529)

New in version 2.0.4 (March 30th, 2010)

  • Browser:
  • Closing browser / switching profile keeps and later restores state / open tabs and history (Bug 486696)
  • MailNews:
  • Null pointer dereference or redundant check in mailnews/mime/src/mimei.cpp. (Bug 532108)
  • gloda indexes while offline, if we startup without a network connection (Bug 533776)
  • Autocomplete - primary email address no longer appears before additional email address (now sorted alphabetically) (Bug 543088)
  • Port Bug 410996 - Answering a news article in a saved search folder not stored under a news account creates mail reply instead of follow-up (Bug 546040)
  • Reply button doesn't launch mail composition window. (Bug 549802)
  • crash [@ nsMsgSearchValidityTable::GetAvailable(int, int, int*)] in matchAll filters using saved search or updating filters (Bug 514945)
  • crash [@ nsImapMailFolder::UpdateImapMailboxInfo(nsIImapProtocol*, nsIMailboxSpec*)] (Bug 531792)
  • Too many .msf file open with many third level folders and Show only subscribed folders unchecked/disabled (Bug 549794)
  • WARNING: goofy tree selection state: two ranges are adjacent!: 'endFirstRange == startRange' with test_delete_multiple_messages_with_first_selected_message_open in test-deletion-with-multiple-displays.js (Bug 540252)
  • crash [@ nsMsgXFViewThread::AddHdr(nsIMsgDBHdr*, int, unsigned int&, nsIMsgDBHdr**)] manipulating messages in virtual folder (Bug 539784)
  • crash [@ NS_strlen(unsigned short const*)] - [@ nsImapProtocol::ShowProgress] with IMAP and Galician locale. (Bug 506669)
  • ChatZilla:
  • Langpack incompatible with SM version > 2.0 (Bug 540842)
  • Certificates & Security Features:
  • Update Mozilla stable branches to NSS 3.12.6 and minimal support for RFC 5746 (Bug 545755)
  • General:
  • [SeaMonkey] FTP file upload not working (Bug 467524)
  • Update Help on Popup Windows preferences (Bug 543332)
  • Remove repetitions (the, of) from Help (Bug 543336)
  • Turning Encryption On and Off is no longer an option, remove it from Help (Bug 543340)
  • Remove last traces of Quick Launch from Help (Bug 545765)
  • # mochitest-plain: intermittent "Test timed out" in security/ssl/mixedcontent tests (test_bug329869.html, test_bug383369.html, test_bug455367.html, test_bug472986.html) (Bug 517938)
  • # Override NSS database path for xulrunner application (Bug 462919)
  • # 'make clean' deletes automationutils.py (Bug 525047)
  • # [Linux] mochitest-plain: layout/xul/base/test/test_resizer.xul needs to report success (Bug 492481)
  • # Crash when pasted selection contains data from java [@libc-2.10.1.so@0x729b8 ][@ nsClipboard::HasDataMatchingFlavors] [@ nsHTMLEditor::HavePrivateHTMLFlavor] (Bug 495392)
  • # crash [@ _pushpopupsenabledstate() ] (Bug 528900)
  • # SwitchProxy triggers a Firefox crash in [@ PL_DHashTableOperate] PREF_PrefIsLocked (Bug 535990)
  • # Print dialog should not display the SVG output option when printing to a file (Bug 546093)
  • Compiling:
  • client.py should error out early if wrong python version (Bug 537571)
  • [Tracking] Resync' configure.in between c-1.9.1 and m-1.9.1 (Bug 496236)
  • Port |Bug 473411 - the rule for DIST_FILES should create dist/bin| to c-c (Bug 543294)
  • Port |Bug 422986 -- make -j2 -f client.mk profiledbuild fails| to comm-central (Bug 543296)
  • Remove MOZ_VALGRIND from comm-central (Bug 545133)
  • Port |Bug 495224 - Builds involving symlinks in the source dir fail to find config/config.mk| to comm-central (Bug 545594)
  • Port |Bug 509319 - Enable FIPS throws uncaught exception in toggleFIPS| to comm-central (Bug 548210)
  • Missing python version check in configure (Bug 548670)
  • Require python >= 2.4 to build Mozilla (and >=2.5 on Windows hosts) (Bug 427750)
  • Fix bsdiff linking for builds compiled with CROSS_COMPILE (Bug 535369)
  • Allow client.py network attempts to restart itself in case of failures (Bug 538528)
  • Package new layers library on shared builds (Bug 549390)
  • Hourly/Nightly builds should have some way to see which changeset was used (Bug 474610)
  • Platform:
  • mochitest-plain: test_domWindowUtils.html fails intermittently (Bug 513146)
  • Scrollbars are not being update using dss.enabled (Bug 546941)
  • vorbis_analysis_headerout calls oggpack_writeclear with uninitialized ogb if !v->backend_state (Bug 550184)
  • TM: Severe performance deterioration of String.match with complex regex (Bug 502058)
  • extend nsIINIParser to allow writing INI files (Bug 541594)
  • Update info should allow more html tags through (Bug 503505)
  • Integrate BrowserScope's HTML editor test suite with Mozilla's mochitest framework (Bug 550569)
  • file drop URIs only accidentally work (Bug 549349)
  • Comment out nsw.gov.au in PSL (Bug 547985)
  • nsPluginHost::TrySetUpPluginInstance() can return with the plugin instance owner holding a non initialized instance. (Bug 533030)
  • Hang [@ nsRegion::InsertInPlace] with position:fixed (Bug 541869)
  • Malian registrar (.ml) allows second-level domains (Bug 544319)
  • crash [@ nsHTMLAnchorElement::UnbindFromTree(int, int)] (Bug 540953)
  • Moving FILE_ILLEGAL_CHARACTERS from nsCRT.h to nsCRTGlue.h for frozen linkages (Bug 537967)
  • C++ style comment in C unit modules/plugin/default/unix/npunix.c (Bug 548213)
  • cp932 encoded messages display as garbage (Bug 542823)

New in version 2.0 Beta 2 (September 14th, 2009)

  • tabbed mail, enabling accounts, folders and even single messages to be opened in tabs inside the Mail & Newsgroups window, as well as enabling the Lightning extension to be installed into SeaMonkey for calendering functionality.
  • a completely renewed default theme on Mac OS X to better fit with the look of Leopard and Snow Leopard,
  • reopening of closed browser windows (Undo Close Window),
  • introduction of simpler interfaces for extension developers (SMILE),
  • and a large number of other, smaller improvements.

New in version 2.0 Alpha 2 (December 11th, 2008)

  • Major Changes:
  • SeaMonkey switched to Toolkit, the same backend Firefox uses internally. Due to this change SeaMonkey is now much closer to Firefox as far as user profiles, add-ons and functionality of user interface elements are concerned.
  • The default location of user profiles has changed. Legacy profiles, e.g. from SeaMonkey 1.x, are migrated automatically, excluding third-party add-ons (extensions and themes). The old profile will not be touched (instead, copies are made).
  • The new Add-on Manager allows to install, update, disable and remove extensions (add-ons), themes and plugins using the same mechanisms Firefox uses. This should ease extension management and development considerably.
  • The first step towards customizable toolbars has been made: The icon size and whether to display icons and/or text can be chosen separately for every major toolbar in in both the browser and MailNews components via their context menu.
  • The MailNews component now includes support for reading RSS and Atom feeds, And the browser detects feeds offered by web pages. Since the support for previewing feeds in the browser has not yet been included, the feed icon at the right end of the URL bar currently is directly invoking subscription to the feed in the MailNews component, if an account for feeds has already been created there.
  • Gecko, the rendering engine used in SeaMonkey, has seen many improvements since the version used in the last stable release. Changes range from a better graphics backend (Cairo/Thebes) to improved support for fonts, CSS, DOM and JavaScript. SeaMonkey 2.0 Alpha 1 passes the Acid2 test and most of Acid3.
  • Most of the icons in the default theme have been exchanged for newer images that fit better with the look of modern desktop environments.
  • Support for Windows 95, 98, Me and NT 4 was dropped. GTK 2.10 is now required on Linux/UNIX. Support for Mac OS X 10.3 ("Panther") was also dropped.
  • Browser:
  • Add Undo Close Tab (Bug 350416, Bug 354953)
  • Introduce Info Bars (e.g. used when popups or add-on installations are blocked) (Bug 270443)
  • Allow to reload individual images using the context menu to aid dialup users canceling page loads (Bug 47475)
  • Remove the font download dialog (Bug 352049)
  • Add full zoom capability (zooming images and objects as well as text) (Bug 4821)
  • Port new Firefox page info to SeaMonkey (Bug 379183)
  • Beautify FTP/File/Jar/Gopher directory listing (with new layout, icons and sortable columns) (Bug 294800)
  • Add "Send This Link" to link context menus (Bug 137007)
  • Save form inputs' state with Save Page As (Bug 293834)
  • Switched to a better graphics backend (Cairo/Thebes), improving display of all web content and application chrome significantly (Bug 322938)
  • Acid2 test renders correctly in most cases (Tracked in Bug 289480)
  • Lots of improvements to Acid3 test rendering (Tracked in Bug 410460)
  • Support WHATWG and tags (Bug 382267)
  • Implement cross-site XMLHttpRequest (Bug 389508)
  • MailNews:
  • Rename TLS and SSL in SMTP preferences to what they really mean (STARTTLS, SMTP-over-SSL) (Bug 185662)
  • Make Reply, Reply All, Forward and Next buttons dual-mode (adding Reply to Sender, Reply to All Recipients, Forward Inline/As Attachment, Next Message/Flagged Message/Unread Thread) (Bug 17796)
  • Do not lose keystrokes while email composer is saving draft (Bug 352310)
  • Speed up deleting attachments containing UNIX line breaks (Bug 365751)
  • Add "Stop Filter Execution" filter action (Bug 358684)
  • Allow to set marking junk as read independently for automatic and manual cases in preferences (Bug 377920)
  • Do not fall back to insecure authentication after SMTP authentication failure (Bug 311657)
  • Support opening a message from the command line (Bug 386919)
  • Remove "Copy Folder Location" context menu entry, moving functionality to Location field in Properties dialog (Bug 369393)
  • Add ability to select IMAP trash folder (Bug 182274)
  • Allow user to reorder newsgroups using drag&drop (like in NS4) (Bug 150274)
  • Display clickable references for newsgroup messages (Bug 62033)
  • Show new newsgroups in Subscribe dialog (Bug 40260)
  • Spell check the subject line when composing mail (Bug 391964)
  • Show folder address in Folder Properties dialog (Bug 180546)
  • Implement mail "back" and "forward" (Bug 74959)
  • Make local body search work when mail body is encoded as Base64 (Bug 132340)
  • Show text in multipart messages with empty Content-Type (sent by Outlook) (Bug 155537)
  • Allow to filter news based on any headers (Bug 16913)
  • Make delete message work if header of message preview pane has focus (Bug 419379)
  • Allow to do a complete import (settings, mail etc.) at any time (Bug 399312)
  • Get rid of the Send in UTF-8 question dialog, just silently switch to UTF-8 if necessary (Bug 410333)
  • Allow to kill/ignore a news subthread (branch, not the whole thread) (Bug 11054)
  • Add "Recent Folder Target" to Move and Copy menus (Bug 416669)
  • Allow renaming of already-attached attachments (Bug 190298)
  • Make sure IMAP code does not deadlock when it cannot reach the network (Bug 410747)
  • Persist message priority across moves after changing it via filter (Bug 181561)
  • Add a pref to decide whether to quote text attachments in replies (Bug 384599)
  • Limit growth of junk token store (and thereby memory) (Bug 228675)
  • Speed up displaying saved searches with lots of results (Bug 436960)
  • Add a way to entirely disable marking a message as read when viewed (Bug 297534)
  • Add ability to show only IMAP mails that have not been deleted (Bug 190974)
  • Load IMAP/news messages from memory (if present) when offline (Bug 213729)
  • Use better chunk size calculation when mail.imap.fetch_by_chunks is active (speed up sending of large emails) (Bug 425849)
  • Quote just the selected portion of a message during Reply (Bug 23394)
  • Allow signature to be placed above the quoted text when forwarding messages (Bug 273114)
  • Improve online IMAP experience by using pseudo-offline Delete and Move (decouple IMAP operations from UI changes) (Bug 435153)
  • Allow filter of "To or CC" to use "is in Address Book..." and "is not in Address Book..." (Bug 187768)
  • Make Get All New Messages work with Movemail accounts (Bug 278383)
  • Enable filters to move mail after copying it (Bug 376235)
  • Add confirmation dialog for Empty Trash action (Bug 179891)
  • Rename 'Unsent' folder to 'Outbox' (Bug 387656)
  • Allow to specify whether to run filters when checking mail, run manually, or both (add a separate manual filter context) (Bug 440635)
  • Add ability to filter only selected messages in a folder (Run Filters on Selected Messages) (Bug 444209)
  • Play back tags to IMAP server when switching from offline to online (Bug 141606)
  • Add ability to show just the name and not the email address in the message pane (Bug 309057)
  • Allow to change IMAP expunge threshold using a pref (Bug 399835)
  • Implement auto-expunge for IMAP mailboxes (Bug 359284)
  • Enable Mac OS X system address book per default and add UI (Bug 397811)
  • Disable JavaScript in MailNews for now (Bug 453943)
  • Make IMAP folders offline by default if they are newly created and mail.server.default.offline_download pref is true (Bug 452615)
  • Add ability to download IMAP messages preemptively/automatically in the background (Bug 436615)
  • Add birthday fields to address book (Bug 13595)
  • Enable threaded/grouped-by-sort views for saved searches across multiple folders (Bug 379806)
  • Fix importing mail from Outlook 2003/2007 (Bug 408323)
  • Port Thunderbird RSS/Atom reader to SeaMonkey (Bug 255834)
  • Allow extensions to add custom filter actions (Bug 419356)
  • Mark message as read when deleting it from local folder (or POP/IMAP when offline) (Bug 463849)
  • Do not collect addresses into Collected Addressed that occur in other ABs (Bug 58769)
  • Certificates:
  • Allow to export certificate or full chain in Certificate Viewer (Bug 315871)
  • Introduce error pages (and ability to create exceptions) for invalid-certificate errors (Bug 327181)
  • Allow configuring used certificate per mail identity (Bug 278549)
  • Implement new security exception handling backend for MailNews (Bug 429843)
  • Introduce new certificate error page which better separates user information from technical details (Bug 463504)
  • ChatZilla:
  • Change Switch Text Direction shortcut to Ctrl+Shift+X (was: Ctrl+Shift+E) (Bug 333570)
  • Do not open multiline input when dropping link in single line input (Bug 332588)
  • Add IRC-Hispano to default network list (Bug 227366)
  • Add IRCnet to default network list (Bug 135926)
  • Allow styling all parts of ChatZilla with motifs (Bug 235169)
  • Allow disabling Bugzilla link detection on a per-channel basis (Bug 349137)
  • Allow to reorder tabs using drag and drop (Bug 194913)
  • Add auto-away feature (Bug 382085)
  • Display WALLOPS messages (Bug 379087)
  • Support multiple selected users with context menu commands (Bug 408527)
  • Display IRCX ONJOIN messages (Bug 303631)
  • Make double clicking user open query view (WHOIS) (Bug 432235)
  • Display all-numeric channel names as links (Bug 433703)
  • Do not discard changes when topic edit mode focus is lost, add Cancel button (Bug 399450)
  • DOM Inspector:
  • Allow inserting/creating new nodes (Bug 112775)
  • Add File / Save DOM As... (Bug 72494)
  • Allow to hide processing instructions (Bug 360898)
  • Show separate menu entries for Inspect Content/Chrome Document (Bug 337069)
  • Add ability to pick open pages (as opposed to open windows) (Bug 109481)
  • Offer DOM Inspector as an add-on on AMO (Bug 271812)
  • Windows:
  • Create a new Windows installer based on NSIS (Bug 351917)
  • Support new shell service for setting SeaMonkey as default application (better Vista integration) (Bug 380347)
  • Remove "turbo mode" (quick launch) (Bug 361682)
  • Make Debug QA and Palm Sync extensions optional in Windows installer (Bug 385377)
  • Make ChatZilla optional in NSIS installer (Bug 409490)
  • Support "? queryterm" from the command line (launch the default search engine and search for 'queryterm') (Bug 408248)
  • Create UI for new shell service (setting as default application and mail/news handler) (Bug 441050)
  • Enable .wdseml (Windows Search indexer) file opening support for Mail/News (better Vista integration) (Bug 433697)
  • Let downloaded files inherit NTFS properties (like permissions, compression, encryption) from parent directory (Bug 224692)
  • Cleanly unload in case of exiting or restarting Windows (Bug 212316)
  • Linux:
  • Let Backspace default to nothing on Linux instead of going back (in history) (Bug 358764)
  • Support startup notification on Linux/UNIX desktops (Bug 223492)
  • Enable native theme (form control etc.) in HTML content on Linux (Bug 329846)
  • Add support for the X Session Management Protocol (XSMP) (Bug 93789)
  • Make Copy Image work on Linux (Bug 21747)
  • Show preview of files in GTK file picker (Bug 396876)
  • Let $http_proxy influence proxy settings (Bug 66057)
  • Respect the user's settings of icons in menus (Bug 415810)
  • Support Internet keys (Bug 66519)
  • Map mouse buttons 8-9 to back/forward (Bug 355477)
  • Use Gnome's native print dialog on Linux (Bug 193001)
  • Remove XPrint (Bug 326716)
  • Enable DBUS by default on Linux (Bug 388743)
  • Bump minimal required GTK2 version to 2.10 (Bug 420040)
  • Allow dragging bookmarks from a folder in the Personal Toolbar (Bug 151336)
  • Map mouse buttons 6-7 to horizontal scrolling on Linux (Bug 423563)
  • Make drag and drop of graphics insert the image instead of the URL (Bug 229327)
  • Make Mark All Read keyboard shortcut Ctrl+Shift+C on Linux (like on Windows; was: Ctrl+Shift+M) (Bug 422757)
  • Allow dragging multiple image files onto editor (Composer; MailNews and stand-alone) window (Bug 428876)
  • Add a globally shared location for plugins (/usr/lib/mozilla/plugins) on Linux/Unix (Bug 440506)
  • Mac OS X:
  • Do not try to import IE favorites on Mac (Bug 433117)
  • Make Cmd+T open a new window when no browser windows are open (Bug 429926)
  • Move caret to beginning/end of url bar or text box when pressing up/down arrow key (Bug 231754)
  • Improve Mac installer (.dmg) (Bug 406448)
  • Implement Mail.app importer in MailNews core (Bug 420472)
  • Implement Mail.app / 4.x Mac Communicator like versions of the "move/copy" menus (Bug 178091)
  • Enable Mac OS X system address book per default and add UI (Bug 397811)
  • Make Dock icon show new mail at the same time as the Growl alert (Bug 459482)
  • Add Growl integration for mail alerts on Mac OS X (Bug 308552)
  • Compiling:
  • Introduce MozillaBuild for Windows (Bug 363079)
  • Make Mozilla compile with Microsoft Visual Studio 2005 (VC8) (Bug 249782)
  • Remove non-Cairo GTK2 gfx code (GTK 1 support and Xprint) (Bug 383889)
  • Build Chatzilla as an extension (Bug 351715)
  • Remove support for --enable-extensions=all (Bug 450015)
  • General:
  • Add "Ignore Word" to inline spellchecker used for editable elements (Bug 354580)
  • Use bullets instead of asterisks to block out password characters (Bug 97811)
  • Make dictionaries part of the locale pack in the installer (Bug 350688)
  • Make a backup copy of prefs.js before overwriting it if there were errors reading it (Bug 361102)
  • Make downloading using "Save Link As..." successful on a link to a page/file that uses HTTP/FTP authentication (Bug 315227)
  • Allow multiple selection of text with Ctrl (Bug 73373)
  • Switch backend from XPFE to Toolkit (Bug 328887)
  • Add command line handlers for Toolkit (makes -remote work on all platforms) (Bug 335550)
  • Update Software Installation preferences pane including options for automatic updates of the application and add-ons (Bug 363700)
  • Remove Appearance / Themes preferences pane (moved to Tools / Add-on Manager) (Bug 372856)
  • Make Debug/QA UI an extension (that can be disabled or removed) (Bug 381343)
  • Offer to migrate Thunderbird profiles (Bug 306175)
  • Use FF/TB's extension mechanism (Add-on Manager and backend) (Bug 272429)
  • Add migrator for old profiles (Mozilla Application Suite and SM 1.0/1.1) (Bug 329744)
  • Replace Quality Feedback Agent by Breakpad crash reporter (Bug 383125)
  • Use FF's form manager (satchel, was: wallet), including form field autocompletion (Bug 304309)
  • Replace MySpell with HunSpell spelling checker (Bug 319778)
  • Provide mechanism to allow users to list, enable and disable plugins in Add-on Manager (Bug 339056)
  • Make text and images translucent while dragging (Bug 178513)
  • Use new English spell checking dictionary (Bug 397150)
  • Enable automatic updates for SeaMonkey (using AUS) (Bug 408190)
  • Make Plugin Finder Service work with SeaMonkey (replacing Null Plugin) (Bug 278831)
  • Disable direct input of filename into file upload controls (Bug 258875)
  • New icon set for "SeaMonkey Default Theme" (Bug 348720)
  • Add sanitize (clear private data) option (Bug 416233)
  • Add new Helper Applications preferences pane (Bug 417590)
  • Integrate addons.mozilla.org (AMO) into Add-ons Manager (Bug 414918)
  • Implement geolocation prompt (notification bar) (Bug 459413)
  • Enable view-source link-browsing (SRC, HREF) (Bug 17612)
  • Use Toolkit Type Ahead Find instead of the old one (Bug 345526)