So, depending on the radio button checked above, unnecessary preferences are disabled in the list
of all the available user preferences below. There you may decide to include (check ) or
else exclude (uncheck ) specific preferences. Do remember that you by the use of this
script will only choose which user_pref("
[pref
name ]",
[value ]);
to be included in the user.js
file! If a box is unchecked, the user_pref
is not included and will have no effect on
the preference whatsoever, i.e. the old pref
in the prefs.js file will hold. Naturally
only an included user_pref
can alter a pref
.
Generating the script code by pressing the left button below the 100 preferences without
fine-tuning them, is believed to result in the best weighing of security/privacy and functionality for your
program. The checked preferences are in principle enhancing security/privacy. By checking
unchecked user preferences, you might reduce functionality or security, so be particular when
fine-tuning.
The preferences that are checked by default are important for security and privacy reasons. By checking
more user preferences your program would be even more secure, but possibly lose some useful
functionality. If you are using a program that are no longer being developed, e.g.
Firefox 1.5, SeaMonkey 1.0, Thunderbird 1.5 you should be better off with version 1.0 of the 100 User
Preferences Script .
GENERAL PREFERENCES
These preferences will have an effect on applications built on the Gecko 1.8.1 code-base,
including but not limited to Firefox 2, Thunderbird 2, and SeaMonkey 1.1 , and
the great majority also apply to older and newer programs alike.
Source roots: The preferences refered to in this section are usually found in the all.js or
security-prefs.js files on the 1.8 branch in the project’s source tree .
1 Client certificate selection
Enforce the asking every time for the selection of a security certificate to present to web sites that
require one. By the resolution of bug 431819 a compromise was
reached concerning the requirement of the application’s prompting in this regard. To keep it always
asking, check this preference, which is unchecked by default (since the result might be an annoying
series of prompts).
user_pref("security.remember_cert_checkbox_default_setting ", );
2-3 Validation
Use OCSP to validate only certificates
that specify an OCSP service URL . Change the value
to 2
only if you apply a particular signing certificate authority and URL to query for
OCSP certificate validation.
user_pref("security.OCSP.enabled ",
1
2
);
Require that the OCSP service is
available, otherwise treat the certificate as not valid. This preference – not
applying to the 1.8 branch – is unchecked by default. For more information, see bug 110161 .
user_pref("security.OCSP.require ", );
4-8 Warning alert messages
Warn when browsing secure/normal pages. The dialogue will let you disable each warning until the next
time you start the browser. The warnings when leaving a secure page, and submitting over an insecure
connection are unchecked by default. For pros and cons about these warnings, see bug 341472 .
user_pref("security.warn_entering_weak ", );
user_pref("security.warn_leaving_secure ", );
user_pref("security.warn_viewing_mixed ", );
user_pref("security.warn_submit_insecure ", );
Do not alert when loading a page that supports encryption. This is the default setting on the
trunk as well.
user_pref("security.warn_entering_secure ", );
9-10 The Master Password
Ask for the master password (if enabled) every 30 minutes by default.
You could change the interval by entering any number of minutes in the second user preference. Change
the value of the first user preference to 1
if the application should ask for the password
every time it’s needed.
user_pref("security.ask_for_password ",
1
2
);
user_pref("security.password_lifetime ", );
11 Disable Java ™
The preference for disabling Java is unchecked by default.
user_pref("security.enable_java ", );
12-13 No cache and no prefetching of Next page
The first user preference (which is unchecked by default) would disable the caching of HTTP documents and the second user preference disables all
link prefetching.
user_pref("network.http.use-cache ", );
user_pref("network.prefetch-next ", );
14-15 Sending referer headers
Do not send referer headers. With the first preference, change the value to 1
if rather
than denying referers altogether, link clicks (but not images) should result in the sending of the
referer. Checking the second user preference would inhibit sending of HTTPS referers to other HTTPS sites. See bugs
1582 and 141641 for caveats about
disabling sending of referer headers. These preferences are unchecked by default.
user_pref("network.http.sendRefererHeader ",
0
1
);
user_pref("network.http.sendSecureXSiteReferrer ", );
16-19 Cookies
There are different views on the matter, so these user preferences are unchecked by default. See
bug 324397 for a reasoning
about the best preference for the application default, now resolved as "Allow All Cookies",
i.e. option value 0
.
The option values available for the first user preference mean:
1 Allow cookies from originating server only
2 Disable all cookies
user_pref("network.cookie.cookieBehavior ",
1
2
);
The application default for preference no 17 is "Accept cookies normally",
i.e. option value 0
, and the others mean:
1 Ask once for cookie per site - check user preference no 18 to avoid an
excess of prompts
2 Accept for current session only
3 Accept for any number of days set in user preference no 19 (90 by default)
user_pref("network.cookie.lifetimePolicy ",
1
2
3
);
user_pref("network.cookie.alwaysAcceptSessionCookies ",
);
user_pref("network.cookie.lifetime.days ", );
20-29 JavaScript and popup windows restrictions
The preference for disabling JavaScript is unchecked by default.
user_pref("javascript.enabled ", );
Scripts should not be able to hide or change the status bar or the context menu.
user_pref("dom.disable_window_status_change ", );
user_pref("dom.event.contextmenu.enabled ", );
Popup windows (created by scripts) should not hide the location bar, have a fixed size, or be
impossible to minimize or close. See bug 337344 for caveats about
the first setting (which is unchecked by default).
user_pref("dom.disable_window_open_feature.location ",
);
user_pref("dom.disable_window_open_feature.resizable ", );
user_pref("dom.disable_window_open_feature.minimizable ", );
user_pref("dom.disable_window_open_feature.close ", );
Block popup windows not created as a result of a mouse click. The value 2
of user
preference no 29 allows whitelisted sites to open popups. To disable popups
for all sites, change the value to 3
.
user_pref("dom.disable_open_during_load ", );
user_pref("dom.disable_open_click_delay ", );
user_pref("privacy.popups.disable_from_plugins ",
2
3
);
The user preferences so far were security or privacy related, and when not seriously tending to reduce
functionality, checked by default. The user preferences below more depends on a matter of taste, and
normally they are not checked. Only if the application default has changed in newer versions, or if the
preference has an obvious security/privacy benefit it is checked by default.
GENERAL PREFERENCES FOR BROWSERS
These preferences will control behaviour of the browser component, but note that some functionality might
be dependent on preferences refered to in the previous section.
Source roots: The preferences refered to in this section are usually found in the all.js or else
the browser-prefs.js and firefox.js files on the 1.8 branch in
the project’s source tree .
30-32 Location Bar features
Disable domain guessing and enable Internet keywords . See a mozilla.org ®
document for information about the implementation of this feature.
user_pref("browser.fixup.alternate.enabled ", );
user_pref("keyword.enabled ", );
Apply automatic filling in of the address in the location bar.
user_pref("browser.urlbar.autoFill ", );
33-36 Controlling the tabs
Do not hide the tab bar when only one tab is open.
user_pref("browser.tabs.autoHide ", );
Open link in a new tab (instead of a new window) when middle-clicked.
user_pref("browser.tabs.opentabfor.middleclick ", );
Prevent tabs opened from links or by other applications from receiving focus.
user_pref("browser.tabs.loadInBackground ", );
user_pref("browser.tabs.loadDivertedInBackground ", );
37-38 Blinking and tipping off
The first preference disables tooltips and the second puts an end to blinking text.
user_pref("browser.chrome.toolbar_tips ", );
user_pref("browser.blink_allowed ", );
39 Inline spellchecking
Disable - option value 0
- automatic inline spellchecking for text entry controls such as
textarea
in HTML , or make it also
available for single line controls - option value 2
.
user_pref("layout.spellcheckDefault ",
0
2
);
The preferences changes in the framed area are there to smooth things a bit by getting rid of possible
annoyances in popular browsers. They will have effect in the browser component in application suites like
SeaMonkey , and in stand-alone browsers, e.g. Firefox and its
derivatives.
PROGRAM SPECIFIC PREFERENCES ‣ FIREFOX ®
These preferences will have an effect in Firefox and all browsers based on it. If nothing
else is stated each preference is valid in the latest release.
Source roots: Firefox specific preferences are found in the firefox.js file in the
project’s source tree .
40 Control the display of domain in the identity box for SSL connections
Firefox 3 includes extra UI to convey
information about a site using SSL to encrypt
communications. Option value 1
will show the effective top-level domain along with the
second-level domain (e.g., mozilla.org) emphasized to the left of the URL in the Location Bar. Use
option value 2
to show the full domain (e.g., bugzilla.mozilla.org). This user
preference is checked by default.
user_pref("browser.identity.ssl_domain_display ",
1
2
);
41 Always show the toolbars and tab strip in fullscreen mode
In fullscreen mode, toolbars and the tab strip may be hidden at the top of the screen and only shown
on mouseover. This preference will keep them in sight, and is checked by default.
user_pref("browser.fullscreen.autohide ", );
42-46 Controlling the tabs
Return to Fx 1.5 defaults. Only show the tab’s close button
at the end of the tabstrip (user preference no 42 ) and give focus to the
adjacent tab on closing a tab (user preference no 43 ).
user_pref("browser.tabs.closeButtons ", );
user_pref("browser.tabs.selectOwnerOnClose ", );
Prevent tabs opened with an item from the bookmarks list from receiving focus.
user_pref("browser.tabs.loadBookmarksInBackground ", );
Have search bar results always open in a new tab.
user_pref("browser.search.openintab ", );
Append a group of tabs instead of replacing the existing tabs.
user_pref("browser.tabs.loadFolderAndReplace ", );
47-48 Download directory
Keep the desktop clean by downloading to the last folder specified for a download, i.e.
value 2, or to the downloads folder, i.e. value 1. Alternatively, check the second user
preference to choose every time where downloads get put.
user_pref("browser.download.folderList ",
1
2
);
user_pref("browser.download.useDownloadDir ", );
49 Page reloading
Disable automatic reload of web pages done by the HTML META refresh tag. This user preference is
checked by default.
user_pref("accessibility.blockautorefresh ", );
50 Export bookmarks as HTML at shutdown
Firefox 3 uses JSON as the format
to store bookmark backups by default. By this preference you switch back to using
bookmarks.html instead. Cp. bug 384370 .
user_pref("browser.bookmarks.autoExportHTML ", );
51 Do not restore the session after a crash
This user preference is for disabling the session restore utility after a crash. See the issues list for
Fx 2 for the relevance of this preference.
user_pref("browser.sessionstore.resume_from_crash ",
);
52 Phishing protection by a third-party provider
Firefox 3 does away with this particular preference to make a third-party provider being
consulted to determine whether a site is phishy. If, however, you are using Firefox 2 ,
you might want to activate the feature.
user_pref("browser.safebrowsing.remoteLookups ", );
53 Do not prefill forms with passwords
If Password manager is enabled, do not automatically fill sign-in forms with known usernames
and passwords; instead, act as though there are multiple usernames/password pairs remembered for the
form (fill password after username has been manually typed). This preference is for Firefox
2 only, but is checked by default.
user_pref("signon.prefillForms ", );
PROGRAM SPECIFIC PREFERENCES ‣ SEAMONKEY ®
These preferences will have an effect in SeaMonkey and browsers based on it. If nothing
else is stated each preference is valid in the latest release.
Source roots: SeaMonkey specific preferences are found in the browser-prefs.js file
in the project’s source tree .
54-56 Location bar behaviour
Turn off location bar popups.
user_pref("browser.urlbar.showPopup ", );
user_pref("browser.urlbar.showSearch ", );
Do not select the text when clicking past it in the location bar.
user_pref("browser.urlbar.clickAtEndSelects ", );
57-60 Controlling the tabs
Append a group of tabs instead of replacing the existing tabs.
user_pref("browser.tabs.loadGroup ", );
Open links from external programs, targeted links and unspecified window.open
calls in
tabs instead of new windows (mimic Fx behaviour).
user_pref("browser.link.open_external ", );
user_pref("browser.link.open_newwindow ", );
user_pref("browser.link.open_newwindow.restriction ",
);
61 The sidebar
Do not automatically open the search sidebar when doing a search.
user_pref("browser.search.opensidebarsearchpanel ", );
62-63 Tooltip previews and menu icons
Disable the tooltip preview of a tab’s contents. Cp. bug 315207 .
user_pref("browser.tabs.tooltippreview.enable ", );
Load site icons/favicons when displaying bookmarks in menus, but only if they have already been
cached. Changing the number to 2
would make the browser always load and show the icons
in menus. (The default behaviour is to never show, i.e. option value 0
.)
user_pref("browser.chrome.load_toolbar_icons ",
1
2
);
MAIL & NEWSGROUPS
The preferences changes in this section are here to control mail management, addressbooks and newsgroups.
Note that some functionality might be dependent on preferences refered to in a previous section.
GENERAL PREFERENCES FOR MAIL CLIENTS
These preferences will have effect in the mail and newsgroups component in application suites like
SeaMonkey , and in stand-alone e-mail clients, e.g. Thunderbird
and its derivatives. Corrections of old behaviour and security/privacy related preferences are checked
by default.
Source roots: Mail & News specific preferences are usually found in the all.js or
mailnews.js files on the 1.8 branch in the project’s source tree .
64-67 Security restrictions and Privacy concerns
Do not allow JavaScript, cookies, plugins or remote images in mail.
user_pref("javascript.allow.mailnews ", );
user_pref("network.cookie.disableCookieForMailNews ", );
user_pref("mailnews.message_display.allow.plugins ", );
user_pref("mailnews.message_display.disable_remote_image ", );
68-71 Return receipts
Never send a return receipt if addressee is not in "To" or "CC", and ask me in other cases. By
checking the first preference return receipts would become disabled altogether, nullifying the effect
of the others (which are checked by default).
The option values available for these preferences mean:
0 Never send
1 Always send
2 Ask me
3 Deny the request (only report.other )
user_pref("mail.mdn.report.enabled ",
);
user_pref("mail.mdn.report.not_in_to_cc ", );
user_pref("mail.mdn.report.outside_domain ",
0
2
);
user_pref("mail.mdn.report.other ",
1
2
3
);
72-73 Collecting addresses
Add e-mail addresses to the Collected addressbook (not to muddle the Personal
addressbook ). By also checking the first preference, address collecting (for outgoing messages)
would be disabled altogether.
user_pref("mail.collect_email_address_outgoing ", );
user_pref("mail.collect_addressbook ", );
74-77 Mail list appearance
Do not remember the last selected message or auto-scroll to a new message.
user_pref("mailnews.remember_selected_message ", );
user_pref("mailnews.scroll_to_new_message ", );
In an application from the 1.8 branch, any click on a column header other than the thread column will
unthread the view. To keep threaded view on (like in TB3/SM2) this preference should be
false
(and it is checked by default).
user_pref("mailnews.thread_pane_column_unthreads ", );
Mark duplicat messages as read. See bug 9413 for information. The
alternative values (numbers) mean:
1 Delete dupes
2 Move Dupes to trash
3 Mark Dupes as Read
user_pref("mail.server.default.dup_action ",
1
2
3
);
78-79 Format=flowed prefs and RFC 2646
Read messages using old style wrapping. By also checking preference no 79
composed messages would be prevented from being transmitted with format=flowed. See Format=Flowed
Mini-FAQ about this feature.
user_pref("mailnews.display.disable_format_flowed_support ", );
user_pref("mailnews.send_plaintext_flowed ", );
80-82 Regular compacting of folders
Compact folders when it will save over a certain amount of kilobytes, by default 100 kB. Do change
the number to any threshhold.
user_pref("mail.prompt_purge_threshhold ", );
user_pref("mail.purge_threshhold ", );
In recent builds the client will show a confirmation alert when starting automatic compacting of
folders. Check the preference if you do not want this alert and you also checked no 80 above.
user_pref("mail.purge.ask ", );
83 Do not check for new mail until the mail client is started
In recent SeaMonkey builds a check for new mail will be done, even when the Mail
& Newsgroups component remains closed. Check this user preference to disable the feature.
user_pref("mail.biff.on_new_window ", );
PROGRAM SPECIFIC PREFERENCES ‣ THUNDERBIRD ™
The preferences in the framed area will have an effect in Thunderbird and e-mail clients
based on it. If nothing else is stated each preference is valid in the latest release.
Source roots: Thunderbird specific preferences are found in the all-thunderbird.js
file in the project’s source tree .
MISCELLANEOUS
The remaining user preferences we need to deal with are diverse annoyances found here and there and they
might or might not have an effect on your software. Privacy related preferences are checked by default.
87-88 Zoom behaviour
Revert to old text size zoom behaviour (not zooming everything on the page). See bug 401322 for more
information.
user_pref("browser.zoom.full ", );
Do not remember zooming on a per-site basis, instead the zoom level should be applied on the current
tab only. Cp. bug 419609 . This preference is
for Firefox 3 only.
user_pref("browser.zoom.siteSpecific ", );
89-91 Handling personal information
Do not save form data, and use encryption when storing sensitive data. The wallet preferences
apply to Thunderbird and Seamonkey .
user_pref("wallet.captureForms ", );
user_pref("wallet.crypto ", );
Do not fill in form data automatically. (This preference does not apply to SeaMonkey 1 .)
user_pref("browser.formfill.enable ", );
92-93 The Password Manager
Checking the first preference would disable the Password manager .
If it is enabled though, do not automatically fill sign-in forms with known usernames and passwords;
instead, act as though there are multiple usernames/password pairs remembered for the form (fill
password after username has been manually typed). (This preference does not apply to the 1.8 branch.)
user_pref("signon.rememberSignons ", );
user_pref("signon.autofillForms ", );
94-95 Ease the handling of self-signed certificates
The first preference enables some extra UI on the SSL error page that makes it easier to accept an invalid
certificate, and the second preference pre-fetches the certificate. See bug 427293 for more
information. (These preferences don’t apply to the 1.8 branch.)
user_pref("browser.xul.error_pages.expert_bad_cert ", );
Note: The user preference above is somewhat jeopardising security.
user_pref("browser.ssl_override_behavior ", );
Note: The user preference above is somewhat jeopardising security.
96-97 Automatic updates
The application should automatically check to see if there is an updated version of itself, but should
prompt before downloading major releases. Checking the first user preference would disable automatic
updates.
user_pref("app.update.auto ", );
Note: The user preference above is somewhat jeopardising security.
user_pref("app.update.mode ", );
98 Uncover the secret add-ons install button
Unhides the install button in the add-ons manager. See Uncover... for a blog entry about this feature.
user_pref("extensions.hideInstallButton ", );
99 Let Windows OS have memory if the application is
minimized
Allow the application to release memory for the benefit of other programs. See bug 76831 for more information.
user_pref("config.trim_on_minimize ", );
100 Show the world
Add a note to the user agent string. Do observe that this user preference is always included.
user_pref("general.useragent.extra.user_js ",
);