You are currently viewing a snapshot of taken on April 21, 2008. Most of this content is highly out of date (some pages haven't been updated since the project began in 1998) and exists for historical purposes only. If there are any pages on this archive site that you think should be added back to, please file a bug.

You are here: browser/composer front-end test cases > Preferences test documentation

Preferences Test Documentation

Maintained by: Sarah Liberman

The Preferences window appears throughout Mozilla and Netscape --in the browser, in mail and news, the editor, and so forth.

Important: As of this writing, this test plan does not cover the backend aspect of preferences. That will probably be covered in another document --if you wish to contribute with that effort (or even this document), please contact me.

Will test

Testing generally covers the areas below. However, please note the exceptions under the Will not test section. Mind you, given that thorough test suites are under continual development, what's covered here and under the Will not test section is subject to change.

Having said that, I should point out that the primary goal of this QA outline is the preferences UI (frontend).

  • Look and feel: visual consistency within the Navigator product. Also, cross platform consistency (with the exception of certain platform specific add-ons).
  • Style, spelling, grammar, etc.
  • Access to all Preference categories (again, dependent on platform) for the Navigator product.
  • Behavior and configurability of user preferences accessible from the Preferences window. This includes testing how/when/whether the browser respects such changes. Specifically, the features in these panels:
    • Appearance
    • Navigator
  • How (and whether!) any user preference accessible from Preferences are written out to configuration files, namely prefs.js in the user's profile directory.
  • Existence and correctness of default preference files for a given installation.

Will NOT test

The following areas will not be covered in detail. Please refer to the appropriate test plan for further information. Note that many bugs here may still fall under the browser Preferences component --it's just that development and test cases is done by other groups. In addition, I've denoted which Bugzilla component these items are likely to fall under; unless otherwise noted, the components are in the Browser product.

  • Fonts. Bugs go into the Style System component.
  • Colors. Bugs go into the Style System component.
  • Themes. Bugs go into the Skinability component if it deals with theme switching. Otherwise, bugs concerning a particular theme go into Themes. Refer to the Themes test case page for additional tests.
  • Languages/Content Packs. Bugs go to Internationalization. Also refer to the International QA test case main page.
  • History. Bugs go into the History component. Also, refer to the History test case page.
  • Languages. Bugs might be rerouted to the Internationalization component. Also refer to the International QA test case main page.
  • Helper Applications. Bugs should be rerouted to the File Handling component, unless they deal specifically with plug-ins. In that case, file bugs in Plug-ins. Also refer to the Helper Applications UI test outline.
  • Smart Browsing. Bugs go into either the Sidebar or Search components.
  • Internet Search. Bugs go into the Search component. Also refer to the Search test case page.
  • Tabbed Browsing. Bugs go to the Tabbed Browser component. Also refer to the Tabbed Browser test outline.
  • Downloads. If the bug occurs only within the download manager window, it should be filed under Download Manager. Otherwise bugs go to File Handling. Also refer to the file saving and download manager QA documents.
  • Composer. Bugs go into the Editor: Composer component. Refer to the Composer Preferences test case page for further details.
  • New Page Settings. Bugs go into the Editor: Composer component. Refer to the Composer Preferences test case page for further details.
  • Functionality and UI problems with the Mail & Newsgroups category (and its subsidiaries below) belong in the MailNews product. There are already several QA documents for these areas: The functional/UI tests and the baseline functional tests.
    • Mail & Newsgroups toplevel panel. Bugs go into the Mail Window Front End component.
    • Windows. Bugs go into the Mail Window Front End component.
    • Message Display. Bugs go into the Mail Window Front End component.
    • Composition. Bugs go into the Composition component.
    • Send Format. Bugs go into the Composition component.
    • Addressing. Address book bugs go into the Address Book component. Directory server bugs go LDAP Mail/News Integration.
    • Labels. Bugs go to either Mail Window Front End or Filters.
    • Return Receipts. Bugs go to Return Receipts.
  • Cookies. Bugs go into the Cookies component.
  • Images. Route bugs to Image Blocking.
  • Pop-ups. Bugs go to either XP Apps or Security: CAPS.
  • Forms. Bugs dealing with the Form Manager go into Form Manager.
  • Passwords. Bugs for the Password Manager go into Password Manager. Bugs for encryption go into the PSM product.
  • Bugs in the following security oriented panels should go to the PSM product. (Test documentation is currently located internally.)
    • Master Passwords
    • SSL
    • Certificates
    • Validation
  • Advanced. Java issues go to OJI. FTP issues to Networking: FTP. Quick Launch issues to Quick Launch.
  • Scripts & Plugins. Scripting issues should go to either DOM Level 0 or Security: CAPS. Plug-in issues to Plug-ins.
  • Cache. Bugs go into the Networking: Cache component. Also refer to the networking QA home and testing overview pages.
  • Proxies. Bugs go into the Networking component. Also refer to the networking QA home and testing overview pages.
  • HTTP Networking. Bugs go to Networking: HTTP. Also refer to the networking QA home and testing overview pages.
  • Software Installation. Bugs go into one of the Installer components. Also refer to the Installation QA document.
  • Mouse Wheel. Bugs go into the XP Toolkit/Widgets component.
  • Mozilla only. DOM Inspector. Bugs go into the DOM Inspector component.
  • Win32 only. System. Bugs go into the XP Apps component.
  • Netscape only. Functionality and UI problems with the Instant Messenger and ICQ categories should be filed within the Preferences component of the Instant Messenger product of Bugscape.
  • Offline & Disk Space. Bugs go to the Offline component of the MailNews product. There are several QA documents covering this feature:

Issues, references & bug information

Remember, the preferences are a moving target that are touched by many engineering and QA groups. This means the UI can change day to day.

Here are some high-level bugs (some for tracking) which give a good overview of pref issues.

  • Bug 33115: Remove obsolete prefs.
  • Bug 80392: Preference panels whose content doesn't fit; also see bug 133627.
  • Bug 114521: (meta) Reorganization / redesign of prefs UI.

So, is there any documentation describing what each and every preference setting in these files is supposed to do? Alas, at the present, no. However, a good reference (for the time being, at least), would be the Netscape developer docs at DevEdge Online. They might not all be exactly identical to the settings used in Mozilla or Netscape 6, since they're primarily written for Communicator 4.x, but it's somewhere to start.

In general, the corresponding Bugzilla component is Preferences in the Browser product. However, bugs might be filed elsewhere --check the Will not test section for additional pointers. Also, check out the Navigator: Who to bug document to see who works on what. Before you file, please make sure the problem you see hasn't already been filed!

Here are some handy Bugzilla links, based on the Preferences component. Again, some of the features described in this plan may or may not be listed under the Preferences component, so if you don't find what you're looking for here, you may need to do a query which covers other components/parameters. Conversely, some bugs from features not covered by this plan might show up in the queries below.

Test coverage

Test coverage will occur on several levels:

  1. Acceptance tests (breadth of functionality)
  2. Functional and stress/boundary/negative tests (depth of functionality):
  3. Ad hoc and regression testing

Acceptance tests

Acceptance testing (aka, baseline functionality) will cover the following items.

  • Open Preferences window from the browser, i.e., Edit > Preferences.
  • Dismiss Preferences window: OK/Cancel buttons, or Enter/Esc keys. Detailed tests for dismissing preferences.
  • Links to basic navigation tests. e.g., Expand and collapse category tree/parent categories.
  • Able to select categories by either a mouse or up/down arrow keys on keyboard.
  • Verify that <profile-directory>/prefs.js is written to after making a preference change. Detailed tests at "how to change and save a preference".
  • Conversely, verify that <profile-directory>/prefs.js is not modified, if preference changes are canceled. Detailed tests at make no changes page.
  • Able to select and view all categories (click link to view screenshot).

Functional & stress/boundary/negative tests: overview, definitions

We are constantly researching ways to either automate and/or more easily create manual tests for Preferences. And when it comes to stress, boundary and negative tests, one could say that the sky's the limit here. :-) What I've come up with (so far) falls under the realm of Torturous means of manipulating the GUI. Goofy as this might sound, this and ad hoc/regression testing are where many bugs are found.

Please contact us if you would like to contribute, offer suggestions, etc. in this effort!

In the meantime, functional UI tests would essentially consist of

  1. Going to given preference panel.
  2. Changing a setting within that panel.
  3. Saving and exiting the Preferences window.
  4. Verifying that, within the appropriate application/component, that the change had been made. Ideally such changes are effective during the same session.
  5. Verifying that the prefs.js file has been properly written/updated (check this file after quitting Mozilla).

Admittedly, this sounds rather open-ended (hence the Request For Contributions).

Some generic examples of functional and stress testing:

  • More navigation tests: More ways to move through preferences!
    • Hold down up/down arrow keys to scroll through category tree. Try quickly scrolling through the category list (e.g., holding down the arrow keys).
    • Use right/left arrow keys to expand/collapse parent categories. Also use Enter/Return key to expand parent categories.
    • Panels:
      • Use tab key to maneuver through textfields, buttons, radiobuttons and checkboxes.
      • Use access keys (mnemonics) to maneuver through various items.
  • Resizing the dialog to extreme sizes; restoring it. Moving the dialog all over and beyond the bounds of the screen/virtual desktop. Repeating ad nauseum.
    • Grab the lower-right corner (typically) of window and drag to resize. Make it really big, really small, etc. Note that you cannot do this when using the Enlightenment window manager on Linux.
  • Entering, cutting, pasting in textfields which should really be disabled.
  • Attempting to enter, cut or paste invalid data to (e.g., image files) or from (e.g., widgets, content associated with widgets) the Preferences window.
  • Changing preferences (front-end). These types of tests increase in complexity.
    • Simple unit testing: Change a single item, and verify that the change is propagated appropriately in the application.
    • Panel testing: Change more than one item, where applicable, in a given panel. Then verify that the changes are propagated appropriately in the application.
    • Multiple panel testing: Change one or more items in more than one preference panel. Then verify that the changes are propagated appropriately in the application.
    • Cancellation: For any of the variations above, cancel your changes, then verify that the changes were not applied.
  • Changing preference (back-end). A couple of things could be done here. Changes are written to prefs.js , however, are most reliably checked after exiting the application
    • After changing something from the Preferences window (UI/front-end), verify the change in either the prefs.js file (setting to a non-default value), or the appropriate default preference file (setting back to a default value).
    • After changing something in the prefs.js file: manually editing --should be done when the application isn't running-- verify that the change has propagated appropriately in the application.
  • Default preference files: Verify existence of the default preference files for a given Mozilla or Netscape installation. They are located in the (install_dir)/defaults/prefs/ directory.

Process for reading preference files

There is more than your basic prefs.js in a profile directory. Here is the order in which the various preference files are read (later read files take higher precedence):

  1. The files located in <install-directory>/defaults/pref/ contains all the default preference settings. These are read first. Descriptions of some of the files:
    • all.js: defaults for the browser and application-wide aspects of Mozilla
    • editor.js: defaults for the editor
    • mailnews.js: defaults for the mail and news readers
    • mdn.js: defaults for mail return receipts
    • psm-glue.js: defaults for security settings
    • macprefs.js: defaults specific to Win32 builds
    • unix.js: defaults specific to unix builds
    • winpref.js: defaults specific to Win32 builds
    • xpinstall.js: defaults for XP installations
  2. If you are running Netscape (commercial), the next file read is all-ns.js. This file contains defaults specific to the commercial builds. Likewise, same with the mailnews-ns.js file.
  3. Your own user profile settings, located in <profile-directory>/prefs.js , are read last and of course should take precedence over the defaults.
  4. If you have a user.js file (also located in <profile-directory>/ ), then this will be read last (after the prefs.js) and take highest precedence. In addition, having this file will render the prefs.jsread-only.


  • If you make any subsequent changes to your own user preferences (from the Preferences UI or by hand) which switch a non-default setting back to a default setting, that particular setting will be removed from your prefs.js. In other words, the defaults would be read from the appropriate files in <install-directory>/defaults/pref/ (including all-ns.js, if you're running the commercial bits).
  • On Mac OS, strings dealing with file paths in the preference files will appear long and obfuscated. This is an expected format, since Mac OS stores file path info as Base64-encoded AliasHandles.

Future QA work: Will add if/when time permits. ;)

  • Denote each specific preference on the back-end for the given options seen in the front-end.
  • Describe hidden preferences, which are seen on the back-end, but don't have a UI (front-end counterpart). Might be best served by the technical documentation group...

Ad hoc & regression testing

Ad hoc testing is covered by users in the Internet community, as well as casual use. Due to time constraints, regression testing will encompass:

  • Verification of Resolved (Fixed ones get priority) bugs as they come in.
  • Periodic verification (e.g., milestone deadlines) of Big Issues to make sure they're still fixed. This would go hand in hand with the usual acceptance testing that occurs during those periods.
  • Ad hoc testing with daily builds.

Detailed panel outline

I've included default settings for reference, where applicable.


  • Choose which Mozilla product(s) to launch on startup. Toggle on (and off) one, two or all three of the applications which would open upon startup:
    • Navigator (on by default)
    • Composer
    • Mozilla Mail
  • Radiobuttons to control toolbars: Pictures and text, Pictures only, Text only. (Still broken in Mozilla trunk?)
  • Toggle on (and off) the checkbox for showing tooltips (on by default).
  • Toggle on (and off) the checkbox for showing web site icons (on by default).


Select the font language (character set) and font styles for your browser.

  • Language encoding droplist (Western by default in US version)
  • Proportional (variable-width) droplist (serif or sans-serif), and its associated font size droplist (pixels). This size will apply to all but the monospace font.
  • Serif font droplist
  • Sans-serif font droplist
  • Cursive font droplist
  • Fantasy font droplist
  • Monospace (fixed-width) droplist, and its associated font size droplist (pixels).
  • "Allow documents to use other fonts" checkbox (selected by default)
  • Screen resolution textfield ("System setting" by default). Selecting "Other" will display a dialog in which to customize the resolution by adding a length value.


Change various color/style settings for how web pages are displayed:

  • Text (foreground) color picker
  • Background color picker
  • "Use System colors" checkbox (off by default)
  • Unvisited Links color picker
  • Visited Links color picker
  • "Underline links" checkbox (on by default)
  • Overriding web page styles (radiobuttons)
    • "Always use the colors and background specified by the web page" (selected by default)
    • "Use my chosen colors, ignoring the colors specified"


Select a theme (chrome and/or skin) for your browser. Unlike in other panels, changes made here (i.e., switching themes) propagate throughout the application before the Preferences window is dismissed.

  • Installed themes listbox. Should at least list Modern and Classic. If you select a theme here, then click OK, you'll be prompted to restart Mozilla for the changes to take effect.
  • Screenshot of the selected theme from the listbox is displayed below the listbox. Below this, there should be information for the theme: its name, author, and a brief description.
  • Uninstall (theme) button. Clicking this will uninstall the theme.
  • Get New Themes link launches a browser window to

Language/Content Packs

There are two listboxes displaying installed content and language packs, respectively. The Download button loads in a browser window.


Change various settings specific to Navigator (i.e., only the web browser window). This is also the default panel displayed when you open the Preferences window from the browser.

  • The initial startup page for the browser window is set by the radiobuttons under "When Navigator starts up, display": Blank page (about:blank), Home page, or Last page visited.
  • The Home page sets the URL for the web page used when you click the Home button in the Personal Toolbar, or select the Go > Home menu item. You can set it three ways:
    • Enter a URL directly in the Location textfield.
    • Use Current Page button should automatically enter what's displayed in the currently active browser window into the Location textfield. Or, if there's more than one, the URL of the browser window from which the Preferences window is launched.
    • Choose File button should launch the file picker and let you select a local file as the home page. Again, the path should be automatically entered into the Location textfield.
    • Restore Default resets to default home page for Mozilla or Netscape.
  • Set options for the toolbars by selecting/deselecting checkboxes:
    • Bookmarks (on by default; Personal Toolbar)
    • Go (off by default; Navigation Toolbar)
    • Home (on by default; Personal Toolbar)
    • Netscape only. My Netscape (on by default; Personal Toolbar)
    • Print (on by default; Navigation Toolbar)
    • Search (on by default; Navigation Toolbar)
    • Toolbar Search
    • Print (Navigation Toolbar)
    • Mail (Personal Toolbar).
    • Netscape only. Shop.
    • Netscape only. IM (Personal Toolbar).
    • Netscape only. Radio (Personal Toolbar).


Browsing (aka, global) history settings:

  • Set expiration (clear) of global history
  • Clear History button explicitly clears global history. This action is done immediately, before exiting the Preferences window (like Themes); can be verified by having the History window up before opening Prefs.

Location bar history menu is the popup which appears to the right of the Location field (aka, URLbar).

  • Clear Location Bar button clears the history for the location bar popup menu which appears to the right of the Location field. As with the Clear History button, this is done immediately, before exiting Preferences.


Select the language preferences for displaying web pages.

  • Move Up/Down allow you to change the preference order of the languages in the listbox for "Languages in order of preference", if there's more than one listed.
  • Add button brings up the Add Languages dialog:
    • Select one or more items from the Languages list box.
    • Manually enter a language's code in the textfield.
    • Additions should then appear in the listbox of the main Languages panel.
  • Remove button removes selected languages from the listbox.
  • For character coding, select from the Default Character Coding droplist (Western (ISO-8859-1) be default for an English-US installation).

Helper Applications

Specify applications for file types; include mime-type information. Mimimal/generic plug-in control. As with Themes, changes made here are immediate, so take place before dismissing the Preferences window.

  • New Type button launches the New Type dialog:
    • Enter a description in the "Description of type" textfield.
    • Enter extension(s) to be recognized in the "File extension" textfield (comma and/or space delimited???).
    • Enter mime info in the "MIME type" textfield.
    • Enter the path of the application or plug-in to use in the "Application to use" textfield:
      • If left blank, Navigator will be used to handle the file type.
      • Alternative to typing in the path to the application: Click the Choose button, which will bring up the file picker, from which you may select the application. This info should then be displayed in the textfield.
  • Edit button launches the Edit Type dialog for the selected file type:
    • (disabled) "Extension" field.
    • "MIME Type" textfield.
    • (Disabled) Checkbox for ""Use this MIME as the outgoing type for these file extensions"
    • Radiobuttons for how the file type is handled:
      • Navigator: When selected, you'll be able to toggle the "Ask me before opening downloaded files of this type" checkbox below (on by default).
      • Save to Disk
      • Enter or edit the path of the application or plug-in to use in the "Application to use" textfield:
        • If left blank, "Save to Disk" will actually be used.
        • Alternative to typing in the path to the application: Click the Choose button, which will bring up the file picker, from which you may select the application. This info should then be displayed in the textfield.
  • Remove button removes the selected item in the "File types" listbox.
  • File Type Details lists information for the item selected in the listbox:
    • Extension
    • MIME type
    • Handled by: Save to disk, Navigator, or Application
  • Opening files: Reset button clears file-opening preferences for ALL mimetype.

Plug-in finder service: a checkbox to enable the Netscape service to obtain plug-ins.

Smart Browsing

Internet Keywords allows quick access to web pages/services/etc. when entering particular keywords in the Location bar:

  • Toggle "Enable Internet Keywords" checkbox (on by default).
  • More Information button launches another web browser window which displays further information about this feature,

Autocompletion for the Location bar:

  • Toggle "Enable Location bar autocomplete" checkbox (on by default).
  • Advanced button brings up advanced autocomplete dialog. Here you can choose among the following checkboxes:
    • Autocomplete best match as you type
    • Show list of matching results
    • Show internet search engine (disabled if list is disabled)
    • Match only web sites you've typed previously (disabled if list is disabled)

Internet Search

The default search engine is the one used when clicking the Search button in the Navigation Toolbar:

  • Select the default engine from the droplist.

You can have search results (via clicking the Search button) pop open the sidebar if it is already closed or minimized.

  • Toggle "Open the Search tab in My Sidebar when search results are available" checkbox (on by default).
  • Toggle Sidebar search preference (radiobuttons): Basic or Advanced.

Tabbed Browsing

Modify your tabbed browsing prefs with the following checkboxes:

  • Hide the tab toolbar when there's only one tab (off by default).
  • Load links in the background (off by default).
  • Open tabs instead of new windows when middle-clicking or accel-clicking links (off by default).
  • Accel-Enter/Return to open a URL from the Location textfield.


Chose the UI for downloading files (radiobuttons):

  • Open the download manager window (default for Win32 and unix).
  • Open a progress dialog (default for Mac OS).
  • Don't open anything.


Set Composer (HTML editor) preferences.

  • Change the maximum number of previously edited web pages listed in the recent pages menu by editing the textfield (10 by default).
  • File saving choice (radiobuttons):
    • "Retain original source formatting".
    • "Reformat ("pretty print") HTML source" (selected by default).
    • Save images and other associated files.
    • Always show Publish dialog.
  • Table editing:
    • Checkbox for "Maintain table layout when inserting or deleting cells" (on by default).
  • Cascading Style Sheets: Checkbox for using CSS instead of HTML elements and attributes (on by default).

New Page Settings

Set preferences for how new pages are handled in Composer.

  • Enter information in the "Author" textfield (fro meta tag info).
  • Default page appearance choice (radiobuttons):
    • Use Composer's default colors, "Reader's default colors" (selected by default)
    • "Use custom colors": Each of the following five items has a color picker associated with it. The selected color is displayed in the listbox on the right side of the panel.
      • Normal text
      • Link text
      • Active link text
      • Visited link text
      • Background
      • In each color picker dialog, you have three ways of changing the color --all results are displayed in the textfield and swatch at the bottom of the dialog.
        • Select a color from the palette, or,
        • Select the "Last picked color" from the droplist, or,
        • Enter a HTML color string (hexcode or name) into the textfield.
  • Specify a background for new web pages by either entering the path in the "Background image" textfield, or via a file picker after clicking the Choose File button. If you use the file picker, the path should also be displayed in the textfield.

Mail & Newsgroups

The Mail and Newsgroups preference panels consist of a toplevel panel, and seven sub-panels: Windows, Message Display, Composition, Send Format, Addressing, Labels and Return Receipts.

There are already several QA documents for these areas: The functional/UI tests and the baseline functional tests.

In addition, there are detailed UI specifications for MailNews Preferences and other related features.


Set how Mozilla handles cookies.

  • Radiobuttons for cookie handling:
    • "Disable cookies"
    • "Enable all cookies" (selected by default for Mozilla).
    • "Enable cookies for the originating site only"
    • Netscape only. "Enable cookies based on privacy settings". The View button launches a dialog where you can choose the levels of privacy.
  • Checkbox for disabling cookies in Mail and Newsgroups (on by default).
  • Checkbox for asking whether a cookie should be stored (off be default). This is selectable only when either "Enable all cookies" or "Enable cookies for the originating site only" is selected.
  • View Stored Cookies button launches the Cookie Manager dialog.
  • Limit maximum lifetime of cookies checkbox (off by default). Associated radiobuttons for "current session" and another for a fixed (user-entered) number of days.


Set how Mozilla handles images.

  • Radiobuttons for cookie handling:
    • "Do not load any images"
    • "Accept all images" (selected by default).
    • Mozilla only. "Accept images that come from the originating server only"
  • Checkbox for loading remote images in Mail and Newsgroup messages (off by default).
  • Mozilla only. Manage Image Permissions button launches the Image Manager dialog.
  • Animated image looping radiobuttons: As many times as specified (default), Once, or Never.


Management of JavaScript-based pop-up windows.

  • Radiobutton allowing all pop-up windows (on by default).
    • Associated checkbox for using custom settings (off by default). When selected, the Manage Popup Permissions button is enabled (where you can chose which sites to disable, as a blacklist).
  • Radiobutton to reject all pop-up windows.


Set preferences for the Form Manager.

  • "Save form pages from web pages when completing forms" (checkbox; on by default). When this is on, the Form Manager will display a dialog asking you if you want to store the form data when you've submitted an HTML form. However, this feature will only work in forms in the top100 sites.
  • Manage Stored Form Data button launches the Form Manager-Editor dialog.
  • Manage Sites button launches the Form Manager-Sites dialog.


Set preferences for the Password Manager.

  • "Remember my passwords for sites that require me to log in" (checkbox; on by default). When this is on, the Password Manager will display a dialog asking you if you want to save your username and password information for both web sites and Mail. If this is off, this dialog will not appear.
  • Manage Stored Passwords button launches the Password Manager dialog.
  • "Use encryption when storing sensitive data" (checkbox; off by default).

Security (PSM)

Test details for the following panels are located on an internal server.

  • Master Passwords
  • SSL
  • Certificates
  • Validation


Set Java and FTP preferences.

  • Enable Java (checkbox; on by default).
  • Send email address as password for anonymous ftp (checkbox; off by default).

Win32 only. Checkbox for enabling Quick Launch.

Scripts & Plug-ins

Various checkboxes to control how JavaScript and plug-ins behave throughout the application.

  • Enable JS for Navigator (on by default).
  • Enable JS for Mail and Newsgroups (off by default).
  • Allow JS to do the following:
    • Mozilla only. Open unrequested windows (pop-ups; on by default). Works with the Pop-up settings.
    • Move or resize existing windows (on by default).
    • Raise or lower windows (on by default).
    • Hide the status bar (on by default).
    • Change status bar text (on by default).
    • Change images (on by default).
    • Create or change cookies (on by default).
    • Read cookies (on by default).
  • Enable plug-ins for Mail and Newsgroups (on by default).


Set cache preferences.

  • Enter value for memory cache in kilobytes (textfield; 4096 Kbytes by default).
  • Clicking Clear Memory Cache button should immediately clear out the cache in memory, i.e., before dismissing the Preferences window.
  • Enter value for disk cache in kilobytes (textfield; 50000 Kbytes by default).
  • Clicking Clear Disk Cache button should immediately clear out the cache on disk, i.e., before dismissing the Preferences window.
  • Disk Cache Folder displays the path of the folder on disk. Can modify this via the Choose Folder button.
  • How to compare the page in cache to the page over the network (radiobuttons):
    • Every time you view the page
    • When the page is out of date (selected by default)
    • Once per session
    • Never


Configure proxy preferences. Select one of the following radiobuttons; edit textfields as needed.

  • Direct connection to the Internet (selected by default).
  • Manual proxy configuration:
    • HTTP proxy and port (two textfields).
    • SSL proxy and port (two textfields).
    • FTP proxy and port (two textfields).
    • Gopher proxy and port (two textfields).
    • SOCKS host and port (two textfields), and associated radiobuttons for the version.
    • No proxy for textfield (takes a comma-delimited list).
  • Automatic proxy configuration via URL
    • Specify URL in the textfield.
    • Reload button reloads the URL immediately, before dismissing Preferences window.

HTTP Networking

Settings for both direct and proxy connections.

  • Direct connections
    • Radiobutton to use either HTTP 1.0 or HTTP 1.1 (1.1 selected by default).
    • Checkbox to enable keep-alive (on by default).
    • Checkbox to enable pipelining (off by default).
  • Proxy connections
    • Radiobutton to use either HTTP 1.0 or HTTP 1.1 (1.1 selected by default).
    • Checkbox to enable keep-alive (on by default).
    • Checkbox to enable pipelining (off by default).

Software Installation

Manage software installations:

  • Checkbox for enabling software installation (allowing XPIs to run?).

Update notifications:

  • Checkbox for checking for updates either weekly or monthly.

Mouse Wheel

Specify what the mouse wheel does for each modifier key. The options below the Modifier key droplist change with respect to what's selected in the droplist.

  • Modifier key droplist:
    • No modifier key
    • Alt key
    • Control key
    • Shift key
  • Radiobutton (selected by default for the "No modifier key", "Control key" and "Shift key" settings): Scroll the document by a given number of lines:
    • Textfield is dependent on the "Use system default" checkbox. The checkbox is on by default, which causes the associated textfield to be disabled (with a value of 1).
  • Radiobutton: Scroll a page up or a page down.
  • Radiobutton (selected by default for the "Alt key" setting): Move back and forward in the browsing history.
  • Radiobutton: Make the text larger or smaller.

Mozilla only. DOM Inspector

Settings for the DOM Inspector application.

  • Checkbox to allow blinking of selected element (on by default).
  • Border color picker.
  • Border width textfield (2px by default).
  • Blink duration textfield (1200ms by default).
  • Blink speed textfield (100ms by default).
  • Button to add the DOM Inspector to your Sidebar.

Win32 only. System

Specify how Mozilla or Netscape should handle various file types and Internet shortcuts (Win32 file associations with Mozilla or Netscape); all are checkboxes.

  • Select which file types you want to view with Mozilla; all are off by default, except where noted.
    • HTML documents (on)
    • XHTML documents (on)
    • XML documents (on)
    • XUL documents
    • JPEG images
    • GIF images
    • PNG images
    • MNG images
    • XBM images
    • BMP images
    • ICO images
  • Select the protocol types you want to view with Mozilla or Netscape; all are off by default, except where noted.
    • http: Hypertext Transfer Protocol (on)
    • https: Secure HTTP (on)
    • ftp: File Transfer Protocol (on)
    • chrome: Chrome Protocol
    • gopher: Gopher Protocol
  • "Check that Windows is set up to match these preferences each time Mozilla starts up" (on by default).


General debugging options; all are checkboxes except where noted.

  • Rendering debug XUL boxes (off by default).
  • Enable JavaScript dump() output (off by default).
  • Show strict JavaScript warnings (off by default).
  • Show JavaScript errors and warnings in the chrome in the JS console (on by default).
  • Use XBL-based form controls (off by default; requires you to exit and restart Mozilla or Netscape to take effect).
  • Use native print dialog (where supported; on by default).
  • Use global print settings (on by default).
  • Keyboard accelerators (value of 0 disables a modifier key).
    • Accelerator key textfield (value): Control for Win32 and unix; Command for Mac OS.
    • Menu access key textfield (value): Alt for Win32 and unix; (?)Control for Mac OS?


Event debugging options; all are checkboxes except where noted. All are off (unselected) by default.

  • Paint flashing (Caps lock key toggles this off and on).
  • Paint dumping.
  • Invalidate dumping.
  • Event dumping.
  • Motion event dumping.
  • Crossing event dumping.
  • Reflow: show frame counts.
  • Reflow: dump frame counts.
  • Reflow: dump frame by frame counts.


Network debugging options.

  • Directory listing format radiobuttons: HTML or XUL (HTML by default). Affects only HTTP and FTP listings; file listings still appear in XUL format as of this writing.
  • Cache debugging checkboxes:
    • Disable XUL cache (off by default).
    • Enable disk cache (on by default).
    • Enable mem cache (on by default).

Offline & Disk Space

There are several QA documents covering this feature: