tor-browser

UrlbarPrefs.sys.mjs (48979B)

---

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/**
* This module exports the UrlbarPrefs singleton, which manages preferences for
* the urlbar. It also provides access to urlbar Nimbus variables as if they are
* preferences, but only for variables with fallback prefs.
*/

import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";

const lazy = XPCOMUtils.declareLazy({
 NimbusFeatures: "resource://nimbus/ExperimentAPI.sys.mjs",
 UrlbarUtils: "moz-src:///browser/components/urlbar/UrlbarUtils.sys.mjs",
 CustomizableUI:
   "moz-src:///browser/components/customizableui/CustomizableUI.sys.mjs",
});

const PREF_URLBAR_BRANCH = "browser.urlbar.";

/**
* @typedef {boolean|number|string|[number, string]} PreferenceDefaultAndType
* Prefs are defined as [pref name, default value] or [pref name, [default
* value, type]]. In the former case, the getter method name is inferred from
* the typeof the default value.
*
* @typedef {[string, PreferenceDefaultAndType]} PreferenceDefinition
*/

// NOTE: Don't name prefs (relative to the `browser.urlbar` branch) the same as
// Nimbus urlbar features. Doing so would cause a name collision because pref
// names and Nimbus feature names are both kept as keys in UrlbarPref's map. For
// a list of Nimbus features, see toolkit/components/nimbus/FeatureManifest.yaml.
const PREF_URLBAR_DEFAULTS = /** @type {PreferenceDefinition[]} */ ([
 // Whether we announce to screen readers when tab-to-search results are
 // inserted.
 ["accessibility.tabToSearch.announceResults", true],

 // Feature gate pref for addon suggestions in the urlbar.
 ["addons.featureGate", false],

 // The number of times the user has clicked the "Show less frequently" command
 // for addon suggestions.
 ["addons.showLessFrequentlyCount", 0],

 // Feature gate pref for AMP suggestions in the urlbar.
 ["amp.featureGate", false],

 // "Autofill" is the name of the feature that automatically completes domains
 // and URLs that the user has visited as the user is typing them in the urlbar
 // textbox.  If false, autofill will be disabled.
 ["autoFill", true],

 // Whether enabling adaptive history autofill. This pref is a fallback for the
 // Nimbus variable `autoFillAdaptiveHistoryEnabled`.
 ["autoFill.adaptiveHistory.enabled", false],

 // Minimum char length of the user's search string to enable adaptive history
 // autofill. This pref is a fallback for the Nimbus variable
 // `autoFillAdaptiveHistoryMinCharsThreshold`.
 ["autoFill.adaptiveHistory.minCharsThreshold", 0],

 // Threshold for use count of input history that we handle as adaptive history
 // autofill. If the use count is this value or more, it will be a candidate.
 // Set the threshold to not be candidate the input history passed approximately
 // 30 days since user input it as the default.
 ["autoFill.adaptiveHistory.useCountThreshold", [0.47, "float"]],

 // Affects the frecency threshold of the autofill algorithm.  The threshold is
 // the mean of all origin frecencies plus one standard deviation multiplied by
 // this value.  See UrlbarProviderPlaces.
 ["autoFill.stddevMultiplier", [0.0, "float"]],

 // Feature gate pref for clipboard suggestions in the urlbar.
 ["clipboard.featureGate", false],

 // Whether to close other panels when the urlbar panel opens.
 // This feature gate exists just as an emergency rollback in case of
 // unexpected issues in Release. We normally want this behavior.
 ["closeOtherPanelsOnOpen", true],

 // Whether to show a link for using the search functionality provided by the
 // active view if the the view utilizes OpenSearch.
 ["contextualSearch.enabled", true],

 // Whether using `ctrl` when hitting return/enter in the URL bar
 // (or clicking 'go') should prefix 'www.' and suffix
 // browser.fixup.alternate.suffix to the URL bar value prior to
 // navigating.
 ["ctrlCanonizesURLs", true],

 // Whether copying the entire URL from the location bar will put a human
 // readable (percent-decoded) URL on the clipboard.
 ["decodeURLsOnCopy", false],

 // The amount of time (ms) to wait after the user has stopped typing before
 // fetching results.  However, we ignore this for the very first result (the
 // "heuristic" result).  We fetch it as fast as possible.
 ["delay", 50],

 // Ensure we use trailing dots for DNS lookups for single words that could
 // be hosts.
 ["dnsResolveFullyQualifiedNames", true],

 // Controls when to DNS resolve single word search strings, after they were
 // searched for. If the string is resolved as a valid host, show a
 // "Did you mean to go to 'host'" prompt.
 // 0 - never resolve; 1 - use heuristics (default); 2 - always resolve
 ["dnsResolveSingleWordsAfterSearch", 0],

 // If Suggest is disabled before these seconds from a search, then send a
 // disable event.
 ["events.disableSuggest.maxSecondsFromLastSearch", 300],

 // If a page is interacted with for less than these seconds, before navigating
 // away via browser chrome, then send a bounce event.
 ["events.bounce.maxSecondsFromLastSearch", 10],

 // Whether the heuristic result is hidden.
 ["experimental.hideHeuristic", false],

 // Comma-separated list of `source.providers` combinations, that are used to
 // determine if an exposure event should be fired. This can be set by a
 // Nimbus variable and is expected to be set via nimbus experiment
 // configuration.
 ["exposureResults", ""],

 // When we send events to (privileged) extensions (urlbar API), we wait this
 // amount of time in milliseconds for them to respond before timing out.
 ["extension.timeout", 400],

 // When we send events to extensions that use the omnibox API, we wait this
 // amount of time in milliseconds for them to respond before timing out.
 ["extension.omnibox.timeout", 3000],

 // When true, `javascript:` URLs are not included in search results.
 ["filter.javascript", true],

 // Feature gate pref for flight status suggestions in the urlbar.
 ["flightStatus.featureGate", false],

 // The minimum prefix length of a flight status keyword the user must type to
 // trigger the suggestion. 0 means the min length should be taken from Nimbus
 // or remote settings.
 ["flightStatus.minKeywordLength", 0],

 // The number of times the user has clicked the "Show less frequently" command
 // for flight status suggestions.
 ["flightStatus.showLessFrequentlyCount", 0],

 // Focus the content document when pressing the Escape key, if there's no
 // remaining typed history.
 ["focusContentDocumentOnEsc", true],

 // Applies URL highlighting and other styling to the text in the urlbar input.
 ["formatting.enabled", true],

 // Whether Firefox Suggest group labels are shown in the urlbar view in en-*
 // locales. Labels are not shown in other locales but likely will be in the
 // future.
 ["groupLabels.enabled", true],

 // Feature gate pref for important-dates suggestions in the urlbar.
 ["importantDates.featureGate", false],

 // Set default intent threshold value of 0.5
 ["intentThreshold", [0.5, "float"]],

 // Whether the results panel should be kept open during IME composition.
 ["keepPanelOpenDuringImeComposition", false],

 // Comma-separated list of result types that should trigger keyword-exposure
 // telemetry. Only applies to results with an `exposureTelemetry` value other
 // than `NONE`.
 ["keywordExposureResults", ""],

 // Feature gate pref for stock market suggestions in the urlbar.
 ["market.featureGate", false],

 // The minimum prefix length of a market keyword the user must type to
 // trigger the suggestion. 0 means the min length should be taken from Nimbus
 // or remote settings.
 ["market.minKeywordLength", 0],

 // The number of times the user has clicked the "Show less frequently" command
 // for Market suggestions.
 ["market.showLessFrequentlyCount", 0],

 // As a user privacy measure, don't fetch results from remote services for
 // searches that start by pasting a string longer than this. The pref name
 // indicates search suggestions, but this is used for all remote results.
 ["maxCharsForSearchSuggestions", 100],

 // The maximum number of form history results to include.
 ["maxHistoricalSearchSuggestions", 0],

 // The maximum number of results in the urlbar popup.
 ["maxRichResults", 10],

 // Feature gate pref for mdn suggestions in the urlbar.
 ["mdn.featureGate", true],

 // Comma-separated list of client variants to send to Merino
 ["merino.clientVariants", ""],

 // The Merino endpoint URL, not including parameters.
 ["merino.endpointURL", "https://merino.services.mozilla.com/api/v1/suggest"],

 // OHTTP config URL for Merino requests.
 ["merino.ohttpConfigURL", ""],

 // OHTTP relay URL for Merino requests.
 ["merino.ohttpRelayURL", ""],

 // Comma-separated list of providers to request from Merino
 ["merino.providers", ""],

 // Timeout for Merino fetches (ms).
 ["merino.timeoutMs", 200],

 // Set default NER threshold value of 0.5
 ["nerThreshold", [0.5, "float"]],

 // Whether addresses and search results typed into the address bar
 // should be opened in new tabs by default.
 ["openintab", false],

 // Once Perplexity has entered search mode at least once,
 // we no longer show the Perplexity onboarding callout.
 // This pref will be set to true when perplexity search mode is detected.
 ["perplexity.hasBeenInSearchMode", false],

 // If disabled, QuickActions will not be included in either the default search
 // mode or the QuickActions search mode.
 ["quickactions.enabled", true],

 // The number of times we should show the actions onboarding label.
 ["quickactions.timesToShowOnboardingLabel", 3],

 // The number of times we have shown the actions onboarding label.
 ["quickactions.timesShownOnboardingLabel", 0],

 // Whether we will match QuickActions within a phrase and not only a prefix.
 ["quickactions.matchInPhrase", true],

 // The minumum amount of characters required for the user to input before
 // matching actions. Setting this to 0 will show the actions in the
 // zero prefix state.
 ["quickactions.minimumSearchString", 3],

 // Whether we show the Actions section in about:preferences.
 ["quickactions.showPrefs", false],

 // When non-zero, this is the character-count threshold (inclusive) for
 // showing AMP suggestions as top picks. If an AMP suggestion is triggered by
 // a keyword at least this many characters long, it will be shown as a top
 // pick.
 ["quicksuggest.ampTopPickCharThreshold", 5],

 // Whether the Firefox Suggest data collection opt-in result is enabled.
 ["quicksuggest.contextualOptIn", false],

 // The last time (as seconds) the user dismissed the Firefox Suggest contextual
 // opt-in result.
 ["quicksuggest.contextualOptIn.lastDismissedTime", 0],

 // Number that the user dismissed the Firefox Suggest contextual opt-in result.
 ["quicksuggest.contextualOptIn.dismissedCount", 0],

 // Period until reshow the Firefox Suggest contextual opt-in result when first dismissed.
 ["quicksuggest.contextualOptIn.firstReshowAfterPeriodDays", 7],

 // Period until reshow the Firefox Suggest contextual opt-in result when second dismissed.
 ["quicksuggest.contextualOptIn.secondReshowAfterPeriodDays", 14],

 // Period until reshow the Firefox Suggest contextual opt-in result when third dismissed.
 ["quicksuggest.contextualOptIn.thirdReshowAfterPeriodDays", 60],

 // Number of impression for the Firefox Suggest contextual opt-in result.
 ["quicksuggest.contextualOptIn.impressionCount", 0],

 // Limit for impression to dismiss the Firefox Suggest contextual opt-in
 // result.
 ["quicksuggest.contextualOptIn.impressionLimit", 20],

 // The first impression time (seconds) for the Firefox Suggest contextual
 // opt-in result.
 ["quicksuggest.contextualOptIn.firstImpressionTime", 0],

 // Days until dismiss the Firefox Suggest contextual opt-in result after first
 // impression.
 ["quicksuggest.contextualOptIn.impressionDaysLimit", 5],

 // Comma-separated list of Suggest dynamic suggestion types to enable.
 ["quicksuggest.dynamicSuggestionTypes", ""],

 // Global toggle for whether the quick suggest feature is enabled, i.e.,
 // sponsored and recommended results related to the user's search string.
 ["quicksuggest.enabled", false],

 // Whether non-sponsored quick suggest results are subject to impression
 // frequency caps. This pref is a fallback for the Nimbus variable
 // `quickSuggestImpressionCapsNonSponsoredEnabled`.
 ["quicksuggest.impressionCaps.nonSponsoredEnabled", false],

 // Whether sponsored quick suggest results are subject to impression frequency
 // caps. This pref is a fallback for the Nimbus variable
 // `quickSuggestImpressionCapsSponsoredEnabled`.
 ["quicksuggest.impressionCaps.sponsoredEnabled", false],

 // JSON'ed object of quick suggest impression stats. Used for implementing
 // impression frequency caps for quick suggest suggestions.
 ["quicksuggest.impressionCaps.stats", ""],

 // If the user has gone through a quick suggest prefs migration, then this
 // pref will have a user-branch value that records the latest prefs version.
 // See `QuickSuggest` for details on each version.
 ["quicksuggest.migrationVersion", 0],

 // Whether Suggest will use the ML backend in addition to Rust.
 ["quicksuggest.mlEnabled", false],

 // NOTE: You should most likely access this pref via its Nimbus variable
 // instead: `UrlbarPrefs.get("quickSuggestOnlineAvailable"). It's listed here
 // mainly so tests can access it easily via `UrlbarPrefs`.
 //
 // Whether online Suggest is available to the user. This is only relevant when
 // Suggest overall is enabled.
 ["quicksuggest.online.available", false],

 // Whether online Suggest is enabled for the user. This is only relevant when
 // Suggest overall is enabled and online Suggest is available to the user.
 ["quicksuggest.online.enabled", true],

 // The last time (as seconds) the user selected 'Not Now' on Realtime
 // suggestion opt-in result.
 ["quicksuggest.realtimeOptIn.notNowTimeSeconds", 0],

 // Period until reshow Realtime suggestion opt-in after selecting "Not Now".
 ["quicksuggest.realtimeOptIn.notNowReshowAfterPeriodDays", 7],

 // The type of Realtime suggestion that the user selected 'Not Now' as CSV.
 ["quicksuggest.realtimeOptIn.notNowTypes", ""],

 // The type of Realtime suggestion that the user selected 'Dismiss' as CSV.
 ["quicksuggest.realtimeOptIn.dismissTypes", ""],

 // Whether Firefox Suggest will use the new Rust backend instead of the
 // original JS backend.
 ["quicksuggest.rustEnabled", true],

 // The Suggest Rust backend will ingest remote settings every N seconds as
 // defined by this pref. Ingestion uses nsIUpdateTimerManager so the interval
 // will persist across app restarts. The default value is 24 hours, same as
 // the interval used by the desktop remote settings client.
 ["quicksuggest.rustIngestIntervalSeconds", 60 * 60 * 24],

 // Which Suggest settings to show in the settings UI. See
 // `QuickSuggest.SETTINGS_UI` for values.
 ["quicksuggest.settingsUi", 0],

 // We only show recent searches within the past 3 days by default.
 // Stored as a string as some code handle timestamp sized int's.
 ["recentsearches.expirationMs", (1000 * 60 * 60 * 24 * 3).toString()],

 // Feature gate pref for recent searches being shown in the urlbar.
 ["recentsearches.featureGate", true],

 // Store the time the last default engine changed so we can only show
 // recent searches since then.
 // Stored as a string as some code handle timestamp sized int's.
 ["recentsearches.lastDefaultChanged", "-1"],

 // The maximum number of recent searches we will show.
 ["recentsearches.maxResults", 5],

 // When true, URLs in the user's history that look like search result pages
 // are styled to look like search engine results instead of the usual history
 // results.
 ["restyleSearches", false],

 // Allow the result menu button to be reached with the Tab key.
 ["resultMenu.keyboardAccessible", true],

 // Feature gate pref for rich suggestions being shown in the urlbar.
 ["richSuggestions.featureGate", true],

 // If true, we show tail suggestions when available.
 ["richSuggestions.tail", true],

 // Disable the urlbar OneOff panel from being shown.
 ["scotchBonnet.disableOneOffs", false],

 // A short-circuit pref to enable all the features that are part of a
 // grouped release.
 ["scotchBonnet.enableOverride", true],

 // Allow searchmode to be persisted as the user navigates the
 // search host.
 ["scotchBonnet.persistSearchMode", false],

 // Feature gate pref for search restrict keywords being shown in the urlbar.
 ["searchRestrictKeywords.featureGate", false],

 // Hidden pref. Disables checks that prevent search tips being shown, thus
 // showing them every time the newtab page or the default search engine
 // homepage is opened.
 ["searchTips.test.ignoreShowLimits", false],

 // Feature gate pref for secondary actions being shown in the urlbar.
 ["secondaryActions.featureGate", false],

 // Maximum number of actions shown.
 ["secondaryActions.maxActionsShown", 3],

 // Alternative switch to tab implementation using secondaryActions.
 ["secondaryActions.switchToTab", false],

 // Whether to show each local search shortcut button in the view.
 ["shortcuts.bookmarks", true],
 ["shortcuts.tabs", true],
 ["shortcuts.history", true],
 ["shortcuts.actions", true],

 // Boolean to determine if the providers defined in `exposureResults`
 // should be displayed in search results. This can be set by a
 // Nimbus variable and is expected to be set via nimbus experiment
 // configuration. For the control branch of an experiment this would be
 // false and true for the treatment.
 ["showExposureResults", false],

 // Whether to show search suggestions before general results.
 ["showSearchSuggestionsFirst", true],

 // If true, show the search term in the Urlbar while on
 // a default search engine results page.
 ["showSearchTerms.enabled", true],

 // Global toggle for whether the show search terms feature
 // can be used at all, and enabled/disabled by the user.
 ["showSearchTerms.featureGate", false],

 // Whether speculative connections should be enabled.
 ["speculativeConnect.enabled", true],

 // If true, top sites may include sponsored ones.
 ["sponsoredTopSites", false],

 // Feature gate pref for realtime sports suggestions in the urlbar.
 ["sports.featureGate", false],

 // The minimum prefix length of sports keyword the user must type to trigger
 // the suggestion. 0 means the min length should be taken from Nimbus or
 // remote settings.
 ["sports.minKeywordLength", 0],

 // The number of times the user has clicked the "Show less frequently" command
 // for sports suggestions.
 ["sports.showLessFrequentlyCount", 0],

 // If `browser.urlbar.addons.featureGate` is true, this controls whether
 // addon suggestions are turned on.
 ["suggest.addons", true],

 // If `browser.urlbar.amp.featureGate` is true, this controls whether AMP
 // suggestions are turned on.
 ["suggest.amp", true],

 // Whether results will include the user's bookmarks.
 ["suggest.bookmark", true],

 // Whether results will include a calculator.
 ["suggest.calculator", false],

 // Whether results will include clipboard results.
 ["suggest.clipboard", true],

 // Whether results will include search engines (e.g. tab-to-search).
 ["suggest.engines", true],

 // If `browser.urlbar.flightStatus.featureGate` is true, this controls whether
 // flight status suggestions are turned on.
 ["suggest.flightStatus", true],

 // Whether results will include the user's history.
 ["suggest.history", true],

 // If `browser.urlbar.importantDates.featureGate` is true, this controls
 // whether important-dates suggestions are turned on.
 ["suggest.importantDates", true],

 // Whether results will include Market suggestions.
 ["suggest.market", true],

 // If `browser.urlbar.mdn.featureGate` is true, this controls whether
 // mdn suggestions are turned on.
 ["suggest.mdn", true],

 // Whether results will include switch-to-tab results.
 ["suggest.openpage", true],

 // Whether results will include QuickActions in the default search mode.
 ["suggest.quickactions", false],

 // Whether results will include Suggest suggestions.
 ["suggest.quicksuggest.all", false],

 // Whether results will include sponsored Suggest suggestions. Only relevant
 // if the `all` pref is true.
 ["suggest.quicksuggest.sponsored", false],

 // Whether results will include Realtime suggestion opt-in result.
 ["suggest.realtimeOptIn", true],

 // If `browser.urlbar.recentsearches.featureGate` is true, this controls whether
 // recentsearches are turned on.
 ["suggest.recentsearches", true],

 // Whether results will include synced tab results. The syncing of open tabs
 // must also be enabled, from Sync preferences.
 ["suggest.remotetab", true],

 // Whether results will include search suggestions.
 ["suggest.searches", false],

 // Whether results will include realtime sports suggestions.
 ["suggest.sports", true],

 // Whether results will include top sites and the view will open on focus.
 ["suggest.topsites", true],

 // If `browser.urlbar.trending.featureGate` is true, this controls whether
 // trending suggestions are turned on.
 ["suggest.trending", true],

 // If `browser.urlbar.weather.featureGate` is true, this controls whether
 // weather suggestions are turned on.
 ["suggest.weather", true],

 // If `browser.urlbar.wikipedia.featureGate` is true, this controls whether
 // Wikipedia suggestions are turned on.
 ["suggest.wikipedia", true],

 // If `browser.urlbar.yelp.featureGate` is true, this controls whether
 // Yelp suggestions are turned on.
 ["suggest.yelp", true],

 // If `browser.urlbar.yelpRealtime.featureGate` is true, this controls whether
 // Yelp realtime suggestions are turned on.
 ["suggest.yelpRealtime", true],

 // Whether history results with the same title and URL excluding the ref
 // will be deduplicated.
 ["deduplication.enabled", true],

 // How old history results have to be to be deduplicated.
 ["deduplication.thresholdDays", 0],

 // semanticHistory search query minLength threshold to be enabled.
 ["suggest.semanticHistory.minLength", 5],

 // When using switch to tabs, if set to true this will move the tab into the
 // active window.
 ["switchTabs.adoptIntoActiveWindow", false],

 // Controls whether searching for open tabs returns tabs from any container
 // or only from the current container.
 ["switchTabs.searchAllContainers", true],

 // The minimum number of characters needed to match a tab group name.
 ["tabGroups.minSearchLength", 1],

 // The number of remaining times the user can interact with tab-to-search
 // onboarding results before we stop showing them.
 ["tabToSearch.onboard.interactionsLeft", 3],

 // The number of times the user has been shown the onboarding search tip.
 ["tipShownCount.searchTip_onboard", 0],

 // The number of times the user has been shown the redirect search tip.
 ["tipShownCount.searchTip_redirect", 0],

 // Feature gate pref for trending suggestions in the urlbar.
 ["trending.featureGate", true],

 // The maximum number of trending results to show while not in search mode.
 ["trending.maxResultsNoSearchMode", 10],

 // The maximum number of trending results to show in search mode.
 ["trending.maxResultsSearchMode", 10],

 // Whether to only show trending results when the urlbar is in search
 // mode or when the user initially opens the urlbar without selecting
 // an engine.
 ["trending.requireSearchMode", false],

 // Remove 'https://' from url when urlbar is focused.
 ["trimHttps", false],

 // Remove redundant portions from URLs.
 ["trimURLs", true],

 // Enable the updated design combining the privacy and shield icon
 // and panels in the Urlbar.
 ["trustPanel.featureGate", false],

 // Whether unit conversion is enabled.
 ["unitConversion.enabled", false],

 // The index where we show unit conversion results.
 ["unitConversion.suggestedIndex", 1],

 // Untrim url, when urlbar is focused.
 // Note: This pref will be removed once the feature is stable.
 ["untrimOnUserInteraction.featureGate", false],

 // Whether or not Unified Search Button is shown always.
 ["unifiedSearchButton.always", false],

 // Feature gate pref for weather suggestions in the urlbar.
 ["weather.featureGate", true],

 // The minimum prefix length of a weather keyword the user must type to
 // trigger the suggestion. 0 means the min length should be taken from Nimbus
 // or remote settings.
 ["weather.minKeywordLength", 0],

 // The number of times the user has clicked the "Show less frequently" command
 // for weather suggestions.
 ["weather.showLessFrequentlyCount", 0],

 // Feature gate pref for Wikipedia suggestions (part of Suggest).
 ["wikipedia.featureGate", false],

 // Feature gate pref for Yelp suggestions in the urlbar.
 ["yelp.featureGate", false],

 // The minimum prefix length of a Yelp keyword the user must type to trigger
 // the suggestion. 0 means the min length should be taken from Nimbus.
 ["yelp.minKeywordLength", 4],

 // Whether Yelp suggestions will be served from the Suggest ML backend instead
 // of Rust.
 ["yelp.mlEnabled", false],

 // Whether Yelp suggestions should be shown as top picks. This is a fallback
 // pref for the `yelpSuggestPriority` Nimbus variable.
 ["yelp.priority", false],

 // Whether to distinguish service type subjects. If true, we show special
 // titile for the suggestion. This is a fallback pref for the
 // `yelpServiceResultDistinction` Nimbus variable.
 ["yelp.serviceResultDistinction", false],

 // The number of times the user has clicked the "Show less frequently" command
 // for Yelp suggestions.
 ["yelp.showLessFrequentlyCount", 0],

 // Feature gate pref for Yelp realtime suggestions in the urlbar.
 ["yelpRealtime.featureGate", false],

 // The minimum prefix length of a Yelp keyword the user must type to trigger
 // the suggestion. 0 means the min length should be taken from Nimbus or remote
 // settings.
 ["yelpRealtime.minKeywordLength", 0],

 // The number of times the user has clicked the "Show less frequently" command
 // for Yelp realtime suggestions.
 ["yelpRealtime.showLessFrequentlyCount", 0],
]);

// This is defined separately to PREF_URLBAR_DEFAULTS, to avoid re-indenting
// the array so that we can preserve blame.
const PREF_URLBAR_DEFAULTS_MAP = new Map(PREF_URLBAR_DEFAULTS);

const PREF_OTHER_DEFAULTS = new Map([
 ["browser.fixup.dns_first_for_single_words", false],
 ["browser.ml.enable", false],
 ["browser.search.openintab", false],
 ["browser.search.suggest.enabled", true],
 ["browser.search.suggest.enabled.private", false],
 ["browser.search.widget.new", false],
 ["keyword.enabled", true],
 ["security.insecure_connection_text.enabled", true],
 ["ui.popup.disable_autohide", false],
]);

// Default values for Nimbus urlbar variables that do not have fallback prefs.
// Variables with fallback prefs do not need to be defined here because their
// defaults are the values of their fallbacks.
const NIMBUS_DEFAULTS = {
 addonsShowLessFrequentlyCap: 0,
 quickSuggestScoreMap: null,
 realtimeMinKeywordLength: null,
 realtimeShowLessFrequentlyCap: null,
 weatherKeywordsMinimumLength: null,
 weatherShowLessFrequentlyCap: null,
 yelpMinKeywordLength: null,
 yelpSuggestNonPriorityIndex: null,
};

// Maps preferences under browser.urlbar.suggest to behavior names, as defined
// in mozIPlacesAutoComplete.
const SUGGEST_PREF_TO_BEHAVIOR = {
 history: "history",
 bookmark: "bookmark",
 openpage: "openpage",
 searches: "search",
};

const PREF_TYPES = new Map([
 ["boolean", "Bool"],
 ["float", "Float"],
 ["number", "Int"],
 ["string", "Char"],
]);

/**
* Builds the default result groups and returns the root group.  Result
* groups determine the composition of results in the muxer, i.e., how they're
* grouped and sorted.  Each group is an object that looks like this:
*
* @typedef {object} ResultGroup
* @property {Values<typeof lazy.UrlbarUtils.RESULT_GROUP>} [group]
*     This is defined only on groups without children, and it determines the
*     result group that the group will contain.
* @property {number} [maxResultCount]
*     An optional maximum number of results the group can contain.  If it's
*     not defined and the parent group does not define `flexChildren: true`,
*     then the max is the parent's max.  If the parent group defines
*     `flexChildren: true`, then `maxResultCount` is ignored.
* @property {boolean} [flexChildren]
*     If true, then child groups are "flexed", similar to flex in HTML.  Each
*     child group should define the `flex` property (or, if they don't, `flex`
*     is assumed to be zero).  `flex` is a number that defines the ratio of a
*     child's result count to the total result count of all children.  More
*     specifically, `flex: X` on a child means that the initial maximum result
*     count of the child is `parentMaxResultCount * (X / N)`, where `N` is the
*     sum of the `flex` values of all children.  If there are any child groups
*     that cannot be completely filled, then the muxer will attempt to overfill
*     the children that were completely filled, while still respecting their
*     relative `flex` values.
* @property {number} [flex]
*     The flex value of the group.  This should be defined only on groups
*     where the parent defines `flexChildren: true`.  See `flexChildren` for a
*     discussion of flex.
* @property {ResultGroup[]} [children]
*     An array of child group objects.
* @property {string} [orderBy]
*     Results should be ordered descending by this payload property.
*
* @param {object} options
* @param {boolean} options.showSearchSuggestionsFirst
*   If true, the suggestions group will come before the general group.
*/
function makeDefaultResultGroups({ showSearchSuggestionsFirst }) {
 /**
  * @type {ResultGroup}
  */
 let rootGroup = {
   children: [
     // heuristic
     {
       maxResultCount: 1,
       children: [
         { group: lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_TEST },
         { group: lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_EXTENSION },
         { group: lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_SEARCH_TIP },
         { group: lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_OMNIBOX },
         { group: lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_ENGINE_ALIAS },
         { group: lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_BOOKMARK_KEYWORD },
         { group: lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_AUTOFILL },
         { group: lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_TOKEN_ALIAS_ENGINE },
         {
           group:
             lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_RESTRICT_KEYWORD_AUTOFILL,
         },
         { group: lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_HISTORY_URL },
         { group: lazy.UrlbarUtils.RESULT_GROUP.HEURISTIC_FALLBACK },
       ],
     },
     // extensions using the omnibox API
     {
       group: lazy.UrlbarUtils.RESULT_GROUP.OMNIBOX,
     },
   ],
 };

 // Prepare the parent group for suggestions and general.
 let mainGroup = {
   flexChildren: true,
   children: [
     // suggestions
     {
       children: [
         {
           flexChildren: true,
           children: [
             {
               // If `maxHistoricalSearchSuggestions` == 0, the muxer forces
               // `maxResultCount` to be zero and flex is ignored, per query.
               flex: 2,
               group: lazy.UrlbarUtils.RESULT_GROUP.FORM_HISTORY,
             },
             {
               flex: 99,
               group: lazy.UrlbarUtils.RESULT_GROUP.RECENT_SEARCH,
             },
             {
               flex: 4,
               group: lazy.UrlbarUtils.RESULT_GROUP.REMOTE_SUGGESTION,
             },
           ],
         },
         {
           group: lazy.UrlbarUtils.RESULT_GROUP.TAIL_SUGGESTION,
         },
       ],
     },
     // general
     {
       group: lazy.UrlbarUtils.RESULT_GROUP.GENERAL_PARENT,
       children: [
         {
           availableSpan: 3,
           group: lazy.UrlbarUtils.RESULT_GROUP.INPUT_HISTORY,
         },
         {
           flexChildren: true,
           children: [
             {
               flex: 1,
               group: lazy.UrlbarUtils.RESULT_GROUP.REMOTE_TAB,
             },
             {
               flex: 2,
               group: lazy.UrlbarUtils.RESULT_GROUP.GENERAL,
               orderBy: "frecency",
             },
             {
               // We show relatively many about-page results because they're
               // only added for queries starting with "about:".
               flex: 2,
               group: lazy.UrlbarUtils.RESULT_GROUP.ABOUT_PAGES,
             },
             {
               flex: 99,
               group: lazy.UrlbarUtils.RESULT_GROUP.RESTRICT_SEARCH_KEYWORD,
             },
           ],
         },
         {
           group: lazy.UrlbarUtils.RESULT_GROUP.INPUT_HISTORY,
         },
       ],
     },
   ],
 };
 if (!showSearchSuggestionsFirst) {
   mainGroup.children.reverse();
 }
 mainGroup.children[0].flex = 2;
 mainGroup.children[1].flex = 1;
 rootGroup.children.push(mainGroup);

 return rootGroup;
}

/**
* Preferences class.  The exported object is a singleton instance.
*/
class Preferences {
 /**
  * Constructor
  */
 constructor() {
   this._map = new Map();
   this.QueryInterface = ChromeUtils.generateQI([
     "nsIObserver",
     "nsISupportsWeakReference",
   ]);

   Services.prefs.addObserver(PREF_URLBAR_BRANCH, this, true);
   for (let pref of PREF_OTHER_DEFAULTS.keys()) {
     Services.prefs.addObserver(pref, this, true);
   }
   this._observerWeakRefs = [];
   this.addObserver(this);

   // These prefs control the value of the shouldHandOffToSearchMode pref. They
   // are exposed as a class variable so UrlbarPrefs observers can watch for
   // changes in these prefs.
   this.shouldHandOffToSearchModePrefs = [
     "keyword.enabled",
     "suggest.searches",
   ];

   lazy.NimbusFeatures.urlbar.onUpdate(() => this._onNimbusUpdate());
 }

 /**
  * Returns the value for the preference with the given name.
  * For preferences in the "browser.urlbar."" branch, the passed-in name
  * should be relative to the branch. It's also possible to get prefs from the
  * PREF_OTHER_DEFAULTS Map, specifying their full name.
  *
  * @param {string} pref
  *        The name of the preference to get.
  * @returns {*} The preference value.
  */
 get(pref) {
   let value = this._map.get(pref);
   if (value === undefined) {
     value = this._getPrefValue(pref);
     this._map.set(pref, value);
   }
   return value;
 }

 /**
  * Sets the value for the preference with the given name.
  * For preferences in the "browser.urlbar."" branch, the passed-in name
  * should be relative to the branch. It's also possible to set prefs from the
  * PREF_OTHER_DEFAULTS Map, specifying their full name.
  *
  * @param {string} pref
  *        The name of the preference to set.
  * @param {*} value The preference value.
  */
 set(pref, value) {
   let { defaultValue, set } = this._getPrefDescriptor(pref);
   if (typeof value != typeof defaultValue) {
     throw new Error(`Invalid value type ${typeof value} for pref ${pref}`);
   }
   set(pref, value);
 }

 /**
  * Adds a value to a preference that handles multiple comma-separated values.
  * Throws an error if the preference does not have a comma-separated value.
  *
  * @param {string} pref
  *   The name of the preference to set.
  * @param {*} value
  *   The preference value.
  */
 add(pref, value) {
   let maybeSet = this._getPrefValue(pref);

   if (!(maybeSet instanceof Set)) {
     throw new Error(
       `The pref ${pref} should handle the values as Set but '${typeof maybeSet}'`
     );
   }

   maybeSet.add(value);
   this.set(pref, [...maybeSet].join(","));
 }

 /**
  * Clears the value for the preference with the given name.
  *
  * @param {string} pref
  *        The name of the preference to clear.
  */
 clear(pref) {
   let { clear } = this._getPrefDescriptor(pref);
   clear(pref);
 }

 /**
  * Returns whether the given preference has a value on the user branch.
  *
  * @param {string} pref
  *   The name of the preference.
  * @returns {boolean}
  *   Whether the pref has a value on the user branch.
  */
 hasUserValue(pref) {
   let { hasUserValue } = this._getPrefDescriptor(pref);
   return hasUserValue(pref);
 }

 /**
  * Gets a pref but allows the `scotchBonnet.enableOverride` pref to
  * short circuit them so one pref can be used to enable multiple
  * features.
  *
  * @param {string} pref
  *        The name of the preference to clear.
  * @returns {*} The preference value.
  */
 getScotchBonnetPref(pref) {
   return this.get("scotchBonnet.enableOverride") || this.get(pref);
 }

 getResultGroups({ context }) {
   // We try to cache result groups so we don't have to rebuild them each time.
   // This key may be modified per each SAP, and will track the cached groups,
   // any additionally used condition must be added to the key.
   let key = context.sapName;
   switch (context.sapName) {
     case "urlbar": {
       let showSearchSuggestionsFirst =
         context.searchString ||
         (!this.get("suggest.trending") &&
           !this.get("suggest.recentsearches"));

       let inSearchEngineMode = !!context.searchMode?.engineName;

       // If we're in a case were search suggestions would be shown first, but not
       // in search engine mode, then just use the user preference.
       if (!inSearchEngineMode && showSearchSuggestionsFirst) {
         showSearchSuggestionsFirst = this.get("showSearchSuggestionsFirst");
       }

       key += showSearchSuggestionsFirst;
       return this.#getOrCacheResultGroups(key, () =>
         makeDefaultResultGroups({ showSearchSuggestionsFirst })
       );
     }
     case "searchbar": {
       // This is a temporary placeholder until searchbar gets its own config.
       return this.#getOrCacheResultGroups(key, () =>
         makeDefaultResultGroups({ showSearchSuggestionsFirst: true })
       );
     }
     case "smartbar": {
       // This is a temporary placeholder until smartbar gets its own config.
       return this.#getOrCacheResultGroups(key, () =>
         makeDefaultResultGroups({ showSearchSuggestionsFirst: false })
       );
     }
     default: {
       throw new Error(`Unknown SAP name: ${context.sapName}`);
     }
   }
 }

 /**
  * Adds a preference observer.  Observers are held weakly.
  *
  * @param {object} observer
  *        An object that may optionally implement one or both methods:
  *         - `onPrefChanged` invoked when one of the preferences listed here
  *           change. It will be passed the pref name.  For prefs in the
  *           `browser.urlbar.` branch, the name will be relative to the branch.
  *           For other prefs, the name will be the full name.
  *         - `onNimbusChanged` invoked when a Nimbus value changes. It will be
  *           passed the name of the changed Nimbus variable and the new value.
  */
 addObserver(observer) {
   this._observerWeakRefs.push(Cu.getWeakReference(observer));
 }

 /**
  * Removes a preference observer.
  *
  * @param {object} observer
  *   An observer previously added with `addObserver()`.
  */
 removeObserver(observer) {
   for (let i = 0; i < this._observerWeakRefs.length; i++) {
     let obs = this._observerWeakRefs[i].get();
     if (obs && obs == observer) {
       this._observerWeakRefs.splice(i, 1);
       break;
     }
   }
 }

 /**
  * Observes preference changes.
  *
  * @param {nsISupports} subject
  *   The subject of the notification.
  * @param {string} topic
  *   The topic of the notification.
  * @param {string} data
  *   The data attached to the notification.
  */
 observe(subject, topic, data) {
   let pref = data.replace(PREF_URLBAR_BRANCH, "");
   if (!PREF_URLBAR_DEFAULTS_MAP.has(pref) && !PREF_OTHER_DEFAULTS.has(pref)) {
     return;
   }
   this.#notifyObservers("onPrefChanged", pref);
 }

 /**
  * Called when a pref tracked by UrlbarPrefs changes.
  *
  * @param {string} pref
  *        The name of the pref, relative to `browser.urlbar.` if the pref is
  *        in that branch.
  */
 onPrefChanged(pref) {
   this._map.delete(pref);

   // Some prefs may influence others.
   switch (pref) {
     case "autoFill.adaptiveHistory.useCountThreshold":
       this._map.delete("autoFillAdaptiveHistoryUseCountThreshold");
       return;
     case "showSearchSuggestionsFirst":
       this.#cachedResultGroups.clear();
       return;
   }

   if (pref.startsWith("suggest.")) {
     this._map.delete("defaultBehavior");
   }

   if (this.shouldHandOffToSearchModePrefs.includes(pref)) {
     this._map.delete("shouldHandOffToSearchMode");
   }
 }

 /**
  * Called when the `NimbusFeatures.urlbar` value changes.
  */
 _onNimbusUpdate() {
   let oldNimbus = this._clearNimbusCache();
   let newNimbus = this._nimbus;

   // Callback to observers having onNimbusChanged.
   let variableNames = new Set(Object.keys(oldNimbus));
   for (let name of Object.keys(newNimbus)) {
     variableNames.add(name);
   }
   for (let name of variableNames) {
     if (
       oldNimbus.hasOwnProperty(name) != newNimbus.hasOwnProperty(name) ||
       oldNimbus[name] !== newNimbus[name]
     ) {
       this.#notifyObservers("onNimbusChanged", name, newNimbus[name]);
     }
   }
 }

 /**
  * Clears cached Nimbus variables. The cache will be repopulated the next time
  * `_nimbus` is accessed.
  *
  * @returns {object}
  *   The value of the cache before it was cleared. It's an object that maps
  *   from variable names to values.
  */
 _clearNimbusCache() {
   let nimbus = this.__nimbus;
   if (nimbus) {
     for (let key of Object.keys(nimbus)) {
       this._map.delete(key);
     }
     this.__nimbus = null;
   }
   return nimbus || {};
 }

 get _nimbus() {
   if (!this.__nimbus) {
     this.__nimbus = lazy.NimbusFeatures.urlbar.getAllVariables({
       defaultValues: NIMBUS_DEFAULTS,
     });
   }
   return this.__nimbus;
 }

 /**
  * Returns the raw value of the given preference straight from Services.prefs.
  *
  * @param {string} pref
  *        The name of the preference to get.
  * @returns {*} The raw preference value.
  */
 _readPref(pref) {
   let { defaultValue, get } = this._getPrefDescriptor(pref);
   return get(pref, defaultValue);
 }

 /**
  * Returns a validated and/or fixed-up value of the given preference.  The
  * value may be validated for correctness, or it might be converted into a
  * different value that is easier to work with than the actual value stored in
  * the preferences branch.  Not all preferences require validation or fixup.
  *
  * The values returned from this method are the values that are made public by
  * this module.
  *
  * @param {string} pref
  *        The name of the preference to get.
  * @returns {*} The validated and/or fixed-up preference value.
  */
 _getPrefValue(pref) {
   switch (pref) {
     case "shortcuts.actions": {
       return this.get("scotchBonnet.enableOverride") && this._readPref(pref);
     }
     case "defaultBehavior": {
       let val = 0;
       for (let type of Object.keys(SUGGEST_PREF_TO_BEHAVIOR)) {
         let behavior = `BEHAVIOR_${SUGGEST_PREF_TO_BEHAVIOR[
           type
         ].toUpperCase()}`;
         val |=
           this.get("suggest." + type) && Ci.mozIPlacesAutoComplete[behavior];
       }
       return val;
     }
     case "shouldHandOffToSearchMode":
       return this.shouldHandOffToSearchModePrefs.some(
         prefName => !this.get(prefName)
       );
     case "autoFillAdaptiveHistoryUseCountThreshold": {
       const nimbusValue =
         this._nimbus.autoFillAdaptiveHistoryUseCountThreshold;
       return nimbusValue === undefined
         ? this.get("autoFill.adaptiveHistory.useCountThreshold")
         : parseFloat(nimbusValue);
     }
     case "exposureResults":
     case "keywordExposureResults":
     case "quicksuggest.dynamicSuggestionTypes":
     case "quicksuggest.realtimeOptIn.dismissTypes":
     case "quicksuggest.realtimeOptIn.notNowTypes":
       return new Set(
         this._readPref(pref)
           .split(",")
           .map(s => s.trim())
           .filter(s => !!s)
       );
   }
   return this._readPref(pref);
 }

 /**
  * Returns a descriptor of the given preference.
  *
  * @param {string} pref The preference to examine.
  * @returns {object} An object describing the pref with the following shape:
  *          { defaultValue, get, set, clear }
  */
 _getPrefDescriptor(pref) {
   let branch = Services.prefs.getBranch(PREF_URLBAR_BRANCH);
   let defaultValue = PREF_URLBAR_DEFAULTS_MAP.get(pref);
   if (defaultValue === undefined) {
     branch = Services.prefs;
     defaultValue = PREF_OTHER_DEFAULTS.get(pref);
     if (defaultValue === undefined) {
       let nimbus = this._getNimbusDescriptor(pref);
       if (nimbus) {
         return nimbus;
       }
       throw new Error("Trying to access an unknown pref " + pref);
     }
   }

   let type;
   if (!Array.isArray(defaultValue)) {
     type = PREF_TYPES.get(typeof defaultValue);
   } else {
     if (defaultValue.length != 2) {
       throw new Error("Malformed pref def: " + pref);
     }
     [defaultValue, type] = defaultValue;
     type = PREF_TYPES.get(type);
   }
   if (!type) {
     throw new Error("Unknown pref type: " + pref);
   }
   return {
     defaultValue,
     get: branch[`get${type}Pref`],
     // Float prefs are stored as Char.
     set: branch[`set${type == "Float" ? "Char" : type}Pref`],
     clear: branch.clearUserPref,
     hasUserValue: branch.prefHasUserValue,
   };
 }

 /**
  * Returns a descriptor for the given Nimbus property, if it exists.
  *
  * @param {string} name
  *   The name of the desired property in the object returned from
  *   NimbusFeatures.urlbar.getAllVariables().
  * @returns {object}
  *   An object describing the property's value with the following shape (same
  *   as _getPrefDescriptor()):
  *     { defaultValue, get, set, clear }
  *   If the property doesn't exist, null is returned.
  */
 _getNimbusDescriptor(name) {
   if (!this._nimbus.hasOwnProperty(name)) {
     return null;
   }
   return {
     defaultValue: this._nimbus[name],
     get: () => this._nimbus[name],
     set() {
       throw new Error(`'${name}' is a Nimbus value and cannot be set`);
     },
     clear() {
       throw new Error(`'${name}' is a Nimbus value and cannot be cleared`);
     },
     hasUserValue() {
       throw new Error(
         `'${name}' is a Nimbus value and does not have a user value`
       );
     },
   };
 }

 /**
  * Return whether or not persisted search terms is enabled.
  *
  * @returns {boolean} true: if enabled.
  */
 isPersistedSearchTermsEnabled() {
   return (
     this.getScotchBonnetPref("showSearchTerms.featureGate") &&
     this.get("showSearchTerms.enabled") &&
     !lazy.CustomizableUI.getPlacementOfWidget("search-container")
   );
 }

 /**
  * @type {Map<string, ResultGroup>}
  * Result groups cached by search access point and params used to build them.
  */
 #cachedResultGroups = new Map();
 #getOrCacheResultGroups(key, builder) {
   let groups = this.#cachedResultGroups.get(key);
   if (!groups) {
     groups = builder();
     this.#cachedResultGroups.set(key, groups);
   }
   return groups;
 }

 #notifyObservers(method, changed, ...rest) {
   for (let i = 0; i < this._observerWeakRefs.length; ) {
     let observer = this._observerWeakRefs[i].get();
     if (!observer) {
       // The observer has been GC'ed, so remove it from our list.
       this._observerWeakRefs.splice(i, 1);
       continue;
     }
     if (method in observer) {
       try {
         observer[method](changed, ...rest);
       } catch (ex) {
         console.error(ex);
       }
     }
     ++i;
   }
 }
}

export var UrlbarPrefs = new Preferences();