chrome/browser/browser_features.cc - chromium/src - Git at Google

 // Copyright 2018 The Chromium Authors
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "chrome/browser/browser_features.h"

 #include "base/feature_list.h"
 #include "build/branding_buildflags.h"
 #include "build/build_config.h"
 #include "build/chromeos_buildflags.h"

 #if BUILDFLAG(IS_WIN)
 #include "chrome/browser/net/system_network_context_manager.h"
 #endif

 namespace features {

 #if BUILDFLAG(IS_WIN)
 // When this feature is enabled, metrics are gathered regarding the performance
 // and reliability of app-bound encryption primitives on a background thread.
 BASE_FEATURE(kAppBoundEncryptionMetrics,
              "AppBoundEncryptionMetrics",
              base::FEATURE_ENABLED_BY_DEFAULT);
 #endif  // BUILDFLAG(IS_WIN)

 // This is used to enable an experiment for modifying confidence cutoff of
 // prerender and preconnect for autocomplete action predictor.
 BASE_FEATURE(kAutocompleteActionPredictorConfidenceCutoff,
              "AutocompleteActionPredictorConfidenceCutoff",
              base::FEATURE_DISABLED_BY_DEFAULT);

 // This flag is used for enabling Bookmark triggered prerendering. See
 // crbug.com/1422819 for more details of Bookmark triggered prerendering.
 BASE_FEATURE(kBookmarkTriggerForPrerender2,
              "BookmarkTriggerForPrerender2",
              base::FEATURE_ENABLED_BY_DEFAULT);

 // Enables Certificate Transparency on Desktop.
 // Enabling CT enforcement requires maintaining a log policy, and the ability to
 // update the list of accepted logs. Embedders who are planning to enable this
 // should first reach out to chrome-certificate-transparency@google.com.
 BASE_FEATURE(kCertificateTransparencyAskBeforeEnabling,
              "CertificateTransparencyAskBeforeEnabling",
 #if BUILDFLAG(GOOGLE_CHROME_BRANDING)
              base::FEATURE_ENABLED_BY_DEFAULT);
 #else
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif  // BUILDFLAG(GOOGLE_CHROME_BRANDING)

 // Enables using the ClosedTabCache to instantly restore recently closed tabs
 // using the "Reopen Closed Tab" button.
 BASE_FEATURE(kClosedTabCache,
              "ClosedTabCache",
              base::FEATURE_DISABLED_BY_DEFAULT);

 // When enabled, a new spare renderer is created at a later time if the previous
 // spare renderer was taken by top chrome WebUI.
 BASE_FEATURE(kDeferredSpareRendererForTopChromeWebUI,
              "DeferredSpareRendererForTopChromeWebUI",
              base::FEATURE_DISABLED_BY_DEFAULT);
 // The delay time to create a new spare renderer since the previous spare
 // renderer is taken. This is not effective when
 // `delay_until_page_stopped_loading` is true.
 const base::FeatureParam<base::TimeDelta> kSpareRendererWarmupDelay{
     &kDeferredSpareRendererForTopChromeWebUI, "delay", base::Seconds(1)};
 // If true, a new spare renderer is not created until the last page stops
 // loading.
 const base::FeatureParam<bool> kSpareRendererWarmupDelayUntilPageStopsLoading{
     &kDeferredSpareRendererForTopChromeWebUI, "delay_until_page_stops_loading",
     false};

 // Destroy profiles when their last browser window is closed, instead of when
 // the browser exits.
 // On Lacros the feature is enabled only for secondary profiles, check the
 // implementation of `ProfileManager::ProfileInfo::FromUnownedProfile()`.
 BASE_FEATURE(kDestroyProfileOnBrowserClose,
              "DestroyProfileOnBrowserClose",
 #if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_MAC) || BUILDFLAG(IS_WIN) || \
     BUILDFLAG(IS_CHROMEOS_LACROS)
              base::FEATURE_ENABLED_BY_DEFAULT);
 #else
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif

 // DestroyProfileOnBrowserClose only covers deleting regular (non-System)
 // Profiles. This flags lets us destroy the System Profile, as well.
 BASE_FEATURE(kDestroySystemProfiles,
              "DestroySystemProfiles",
              base::FEATURE_DISABLED_BY_DEFAULT);

 // Let the DevTools front-end query an AIDA endpoint for explanations and
 // insights regarding console (error) messages.
 BASE_FEATURE(kDevToolsConsoleInsights,
              "DevToolsConsoleInsights",
              base::FEATURE_DISABLED_BY_DEFAULT);
 const base::FeatureParam<std::string> kDevToolsConsoleInsightsAidaScope{
     &kDevToolsConsoleInsights, "aida_scope", /*default*/ ""};
 const base::FeatureParam<std::string> kDevToolsConsoleInsightsAidaEndpoint{
     &kDevToolsConsoleInsights, "aida_endpoint", /*default*/ ""};
 const base::FeatureParam<std::string> kDevToolsConsoleInsightsModelId{
     &kDevToolsConsoleInsights, "aida_model_id", /*default*/ ""};
 const base::FeatureParam<double> kDevToolsConsoleInsightsTemperature{
     &kDevToolsConsoleInsights, "aida_temperature", /*default*/ 0.2};
 const base::FeatureParam<bool> kDevToolsConsoleInsightsOptIn{
     &kDevToolsConsoleInsights, "opt_in", /*default*/ true};

 // Separate dogfood feature for DevTools console insights,
 // not restricted by enterprise policy or location.
 BASE_FEATURE(kDevToolsConsoleInsightsDogfood,
              "DevToolsConsoleInsightsDogfood",
              base::FEATURE_DISABLED_BY_DEFAULT);
 const base::FeatureParam<std::string> kDevToolsConsoleInsightsDogfoodAidaScope{
     &kDevToolsConsoleInsightsDogfood, "aida_scope", /*default*/ ""};
 const base::FeatureParam<std::string>
     kDevToolsConsoleInsightsDogfoodAidaEndpoint{
         &kDevToolsConsoleInsightsDogfood, "aida_endpoint", /*default*/ ""};
 const base::FeatureParam<std::string> kDevToolsConsoleInsightsDogfoodModelId{
     &kDevToolsConsoleInsightsDogfood, "aida_model_id", /*default*/ ""};
 const base::FeatureParam<double> kDevToolsConsoleInsightsDogfoodTemperature{
     &kDevToolsConsoleInsightsDogfood, "aida_temperature", /*default*/ 0.2};
 const base::FeatureParam<bool> kDevToolsConsoleInsightsDogfoodOptIn{
     &kDevToolsConsoleInsightsDogfood, "opt_in", /*default*/ true};

 // Whether DevTools shows the setting for console insights. The setting can be
 // shown in a disabled state, even if the feature itself is not available.
 BASE_FEATURE(kDevToolsConsoleInsightsSettingVisible,
              "DevToolsConsoleInsightsSettingVisible",
              base::FEATURE_DISABLED_BY_DEFAULT);
 const base::FeatureParam<std::string>
     kDevToolsConsoleInsightsSettingVisibleBlockedReason{
         &kDevToolsConsoleInsightsSettingVisible, "blocked_reason",
         /*default*/ ""};

 // Whether an infobar is shown when the process is shared.
 BASE_FEATURE(kDevToolsSharedProcessInfobar,
              "DevToolsSharedProcessInfobar",
              base::FEATURE_ENABLED_BY_DEFAULT);

 // Let DevTools front-end talk to the target of type "tab" rather than
 // "frame" when inspecting a WebContents.
 BASE_FEATURE(kDevToolsTabTarget,
              "DevToolsTabTarget",
              base::FEATURE_ENABLED_BY_DEFAULT);

 // Let DevTools front-end log extensive VisualElements-style UMA metrics for
 // impressions and interactions.
 BASE_FEATURE(kDevToolsVeLogging,
              "DevToolsVeLogging",
              base::FEATURE_ENABLED_BY_DEFAULT);

 #if BUILDFLAG(IS_CHROMEOS)
 // Enables being able to zoom a web page by double tapping in Chrome OS tablet
 // mode.
 BASE_FEATURE(kDoubleTapToZoomInTabletMode,
              "DoubleTapToZoomInTabletMode",
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif

 #if BUILDFLAG(IS_WIN)
 // When this feature is enabled, the DPAPI encryption provider will be
 // registered and enabled for encryption/decryption. This provider is
 // forwards/backwards compatible with OSCrypt sync.
 BASE_FEATURE(kEnableDPAPIEncryptionProvider,
              "EnableDPAPIEncryptionProvider",
              base::FEATURE_ENABLED_BY_DEFAULT);

 // When this feature is enabled, the App-Bound encryption provider is registered
 // with Chrome.
 BASE_FEATURE(kRegisterAppBoundEncryptionProvider,
              "RegisterAppBoundEncryptionProvider",
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif  // BUILDFLAG(IS_WIN)

 // Enables usage of the FedCM API without third party cookies at the same time.
 BASE_FEATURE(kFedCmWithoutThirdPartyCookies,
              "FedCmWithoutThirdPartyCookies",
              base::FEATURE_DISABLED_BY_DEFAULT);

 // Enables showing the email of the flex org admin that setup CBCM in the
 // management disclosures.
 BASE_FEATURE(kFlexOrgManagementDisclosure,
              "FlexOrgManagementDisclosure",
 #if BUILDFLAG(IS_CHROMEOS)
              base::FEATURE_DISABLED_BY_DEFAULT);
 #else
              base::FEATURE_ENABLED_BY_DEFAULT);
 #endif  // BUILDFLAG(IS_CHROMEOS)

 // Enables the Incoming Call Notifications scenario. When created by an
 // installed origin, an incoming call notification should have increased
 // priority, colored buttons, a ringtone, and a default "close" button.
 // Otherwise, if the origin is not installed, it should behave like the default
 // notifications, but with the added "Close" button. See
 // https://github.com/MicrosoftEdge/MSEdgeExplainers/blob/main/Notifications/notifications_actions_customization.md
 BASE_FEATURE(kIncomingCallNotifications,
              "IncomingCallNotifications",
              base::FEATURE_DISABLED_BY_DEFAULT);

 // Controls whether the static key pinning list can be updated via component
 // updater.
 BASE_FEATURE(kKeyPinningComponentUpdater,
              "KeyPinningComponentUpdater",
              base::FEATURE_ENABLED_BY_DEFAULT);

 BASE_FEATURE(kLargeFaviconFromGoogle,
              "LargeFaviconFromGoogle",
              base::FEATURE_DISABLED_BY_DEFAULT);
 const base::FeatureParam<int> kLargeFaviconFromGoogleSizeInDip{
     &kLargeFaviconFromGoogle, "favicon_size_in_dip", 128};

 #if BUILDFLAG(IS_WIN)
 // Enables locking the cookie database for profiles.
 // TODO(crbug.com/1430226): Remove after fully launched.
 BASE_FEATURE(kLockProfileCookieDatabase,
              "LockProfileCookieDatabase",
              base::FEATURE_ENABLED_BY_DEFAULT);
 #endif  // BUILDFLAG(IS_WIN)

 #if !BUILDFLAG(IS_ANDROID)
 // Adds a "Snooze" action to mute notifications during screen sharing sessions.
 BASE_FEATURE(kMuteNotificationSnoozeAction,
              "MuteNotificationSnoozeAction",
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif

 // This feature enables monitoring of first-party network requests in order to
 // find possible violations. Example: A Chrome policy is set to disabled but the
 // network request controlled by that policy is observed.
 BASE_FEATURE(kNetworkAnnotationMonitoring,
              "NetworkAnnotationMonitoring",
              base::FEATURE_DISABLED_BY_DEFAULT);

 // This flag is used for enabling New Tab Page triggered prerendering. See
 // crbug.com/1462832 for more details of New Tab Page triggered prerendering.
 BASE_FEATURE(kNewTabPageTriggerForPrerender2,
              "NewTabPageTriggerForPrerender2",
              base::FEATURE_DISABLED_BY_DEFAULT);

 #if BUILDFLAG(IS_WIN)
 // Don't call the Win32 API PrefetchVirtualMemory when loading chrome.dll inside
 // non-browser processes. This is done by passing flags to these processes. This
 // prevents pulling the entirety of chrome.dll into physical memory (albeit only
 // pri-2 physical memory) under the assumption that during chrome execution,
 // portions of the DLL which are used will already be present, hopefully leading
 // to less needless memory consumption.
 BASE_FEATURE(kNoPreReadMainDll,
              "NoPreReadMainDll",
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif  // BUILDFLAG(IS_WIN)

 #if BUILDFLAG(IS_ANDROID)
 // Adds an "Unsubscribe" action to web push notifications that allows stopping
 // notifications from a given origin with a single tap (with an option to undo).
 BASE_FEATURE(kNotificationOneTapUnsubscribe,
              "NotificationOneTapUnsubscribe",
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif

 // Enables omnibox trigger no state prefetch. Only one of
 // kOmniboxTriggerForPrerender2 or kOmniboxTriggerForNoStatePrefetch can be
 // enabled in the experiment. If both are enabled, only
 // kOmniboxTriggerForPrerender2 takes effect.
 // TODO(crbug.com/1267731): Remove this flag once the experiments are completed.
 BASE_FEATURE(kOmniboxTriggerForNoStatePrefetch,
              "OmniboxTriggerForNoStatePrefetch",
              base::FEATURE_DISABLED_BY_DEFAULT);

 // This flag is used for enabling Omnibox triggered prerendering. See
 // crbug.com/1166085 for more details of Omnibox triggered prerendering.
 BASE_FEATURE(kOmniboxTriggerForPrerender2,
              "OmniboxTriggerForPrerender2",
              base::FEATURE_ENABLED_BY_DEFAULT);

 #if BUILDFLAG(IS_CHROMEOS)
 // Enables AES keys support in the chrome.enterprise.platformKeys and
 // chrome.platformKeys APIs. The new operations include `sign`, `encrypt` and
 // `decrypt`. For additional details, see the proposal tracked in b/288880151.
 BASE_FEATURE(kPlatformKeysAesEncryption,
              "PlatformKeysAesEncryption",
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif  // BUILDFLAG(IS_CHROMEOS)

 // Disables prerendering on the default search engine predictor. This is useful
 // in comparing the impact of the SupportSearchSuggestionForPrerender2 feature
 // during its rollout. Once that rollout is complete, this feature should be
 // removed and instead we should add a new long-term holdback to
 // PreloadingConfig.
 BASE_FEATURE(kPrerenderDSEHoldback,
              "PrerenderDSEHoldback",
              base::FEATURE_DISABLED_BY_DEFAULT);

 // Enables executing the browser commands sent by the NTP promos.
 BASE_FEATURE(kPromoBrowserCommands,
              "PromoBrowserCommands",
              base::FEATURE_ENABLED_BY_DEFAULT);

 // Parameter name for the promo browser command ID provided along with
 // kPromoBrowserCommands.
 // The value of this parameter should be parsable as an unsigned integer and
 // should map to one of the browser commands specified in:
 // ui/webui/resources/js/browser_command/browser_command.mojom
 const char kBrowserCommandIdParam[] = "BrowserCommandIdParam";

 #if BUILDFLAG(IS_CHROMEOS_ASH)
 // Enables reading and writing PWA notification permissions from quick settings
 // menu.
 BASE_FEATURE(kQuickSettingsPWANotifications,
              "QuickSettingsPWA",
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif

 #if !BUILDFLAG(IS_ANDROID)
 // Keeps accessibility enabled for WebContents as ReadAnything observes changes
 // to the active WebContents. This is a holdback study to evaluate the impact of
 // the new behavior, whereby the accessibility modes required by ReadyAnything
 // are cleared on a WebContents when ReadAnything loses interest in it.
 BASE_FEATURE(kReadAnythingPermanentAccessibility,
              "ReadAnythingPermanentAccessibility",
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif

 // When this feature is enabled, the network service will restart unsandboxed if
 // a previous attempt to launch it sandboxed failed.
 BASE_FEATURE(kRestartNetworkServiceUnsandboxedForFailedLaunch,
              "RestartNetworkServiceUnsandboxedForFailedLaunch",
              base::FEATURE_ENABLED_BY_DEFAULT);

 // Gates sandboxed iframe navigation toward external protocol behind any of:
 // - allow-top-navigation
 // - allow-top-navigation-to-custom-protocols
 // - allow-top-navigation-with-user-gesture (+ user gesture)
 // - allow-popups
 //
 // Motivation:
 // Developers are surprised that a sandboxed iframe can navigate and/or
 // redirect the user toward an external application.
 // General iframe navigation in sandboxed iframe are not blocked normally,
 // because they stay within the iframe. However they can be seen as a popup or
 // a top-level navigation when it leads to opening an external application. In
 // this case, it makes sense to extend the scope of sandbox flags, to block
 // malvertising.
 //
 // Implementation bug: https://crbug.com/1253379
 // I2S: https://groups.google.com/a/chromium.org/g/blink-dev/c/-t-f7I6VvOI
 //
 // Enabled in M103. Flag to be removed in M106
 BASE_FEATURE(kSandboxExternalProtocolBlocked,
              "SandboxExternalProtocolBlocked",
              base::FEATURE_ENABLED_BY_DEFAULT);
 // Enabled in M100. Flag to be removed in M106
 BASE_FEATURE(kSandboxExternalProtocolBlockedWarning,
              "SandboxExternalProtocolBlockedWarning",
              base::FEATURE_ENABLED_BY_DEFAULT);

 // This flag controls whether to trigger prerendering when the default search
 // engine suggests to prerender a search result.
 BASE_FEATURE(kSupportSearchSuggestionForPrerender2,
              "SupportSearchSuggestionForPrerender2",
 #if BUILDFLAG(IS_CHROMEOS_ASH) || BUILDFLAG(IS_CHROMEOS_LACROS) || \
     BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_MAC) || BUILDFLAG(IS_WIN)
              base::FEATURE_ENABLED_BY_DEFAULT);
 #else
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif
 const base::FeatureParam<SearchPreloadShareableCacheType>::Option
     search_preload_shareable_cache_types[] = {
         {SearchPreloadShareableCacheType::kEnabled, "enabled"},
         {SearchPreloadShareableCacheType::kDisabled, "disabled"}};
 const base::FeatureParam<SearchPreloadShareableCacheType>
     kSearchPreloadShareableCacheTypeParam{
         &kSupportSearchSuggestionForPrerender2, "shareable_cache",
         SearchPreloadShareableCacheType::kEnabled,
         &search_preload_shareable_cache_types};

 // Enables migration of the network context data from `unsandboxed_data_path` to
 // `data_path`. See the explanation in network_context.mojom.
 BASE_FEATURE(kTriggerNetworkDataMigration,
              "TriggerNetworkDataMigration",
 #if BUILDFLAG(IS_WIN)
              base::FEATURE_ENABLED_BY_DEFAULT
 #else
              base::FEATURE_DISABLED_BY_DEFAULT
 #endif
 );

 #if BUILDFLAG(IS_CHROMEOS)
 // If enabled, a blue border is drawn around shared tabs on ChromeOS.
 // If disabled, the blue border is not used on ChromeOS.
 //
 // Motivation:
 //  The blue border behavior used to cause problems on ChromeOS - see
 //  crbug.com/1320262 for Ash (fixed) and crbug.com/1030925 for Lacros
 //  (relatively old bug - we would like to observe whether it's still
 //  there). This flag is introduced as means of disabling this feature in case
 //  of possible future regressions.
 //
 // TODO(crbug.com/1251999): Remove this flag once we confirm that blue border
 // works fine on ChromeOS.
 //
 // b/279051234: We suspect the tab sharing blue border may cause a bad issue
 // on ChromeOS where a window can not be interacted at all. Disable the feature
 // on ChromeOS.
 BASE_FEATURE(kTabCaptureBlueBorderCrOS,
              "TabCaptureBlueBorderCrOS",
              base::FEATURE_DISABLED_BY_DEFAULT);
 #endif

 #if BUILDFLAG(IS_WIN)
 // When this feature is enabled, the network service will be passed an
 // OSCryptAsync crypto cookie delegate meaning that OSCryptAsync will be used
 // for cookie encryption.
 BASE_FEATURE(kUseOsCryptAsyncForCookieEncryption,
              "UseOsCryptAsyncForCookieEncryption",
              base::FEATURE_ENABLED_BY_DEFAULT);
 #endif  // BUILDFLAG(IS_WIN)

 // Enables runtime detection of USB devices which provide a WebUSB landing page
 // descriptor.
 BASE_FEATURE(kWebUsbDeviceDetection,
              "WebUsbDeviceDetection",
              base::FEATURE_ENABLED_BY_DEFAULT);

 }  // namespace features
	// Copyright 2018 The Chromium Authors
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "chrome/browser/browser_features.h"

	#include "base/feature_list.h"
	#include "build/branding_buildflags.h"
	#include "build/build_config.h"
	#include "build/chromeos_buildflags.h"

	#if BUILDFLAG(IS_WIN)
	#include "chrome/browser/net/system_network_context_manager.h"
	#endif

	namespace features {

	#if BUILDFLAG(IS_WIN)
	// When this feature is enabled, metrics are gathered regarding the performance
	// and reliability of app-bound encryption primitives on a background thread.
	BASE_FEATURE(kAppBoundEncryptionMetrics,
	"AppBoundEncryptionMetrics",
	base::FEATURE_ENABLED_BY_DEFAULT);
	#endif // BUILDFLAG(IS_WIN)

	// This is used to enable an experiment for modifying confidence cutoff of
	// prerender and preconnect for autocomplete action predictor.
	BASE_FEATURE(kAutocompleteActionPredictorConfidenceCutoff,
	"AutocompleteActionPredictorConfidenceCutoff",
	base::FEATURE_DISABLED_BY_DEFAULT);

	// This flag is used for enabling Bookmark triggered prerendering. See
	// crbug.com/1422819 for more details of Bookmark triggered prerendering.
	BASE_FEATURE(kBookmarkTriggerForPrerender2,
	"BookmarkTriggerForPrerender2",
	base::FEATURE_ENABLED_BY_DEFAULT);

	// Enables Certificate Transparency on Desktop.
	// Enabling CT enforcement requires maintaining a log policy, and the ability to
	// update the list of accepted logs. Embedders who are planning to enable this
	// should first reach out to chrome-certificate-transparency@google.com.
	BASE_FEATURE(kCertificateTransparencyAskBeforeEnabling,
	"CertificateTransparencyAskBeforeEnabling",
	#if BUILDFLAG(GOOGLE_CHROME_BRANDING)
	base::FEATURE_ENABLED_BY_DEFAULT);
	#else
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif // BUILDFLAG(GOOGLE_CHROME_BRANDING)

	// Enables using the ClosedTabCache to instantly restore recently closed tabs
	// using the "Reopen Closed Tab" button.
	BASE_FEATURE(kClosedTabCache,
	"ClosedTabCache",
	base::FEATURE_DISABLED_BY_DEFAULT);

	// When enabled, a new spare renderer is created at a later time if the previous
	// spare renderer was taken by top chrome WebUI.
	BASE_FEATURE(kDeferredSpareRendererForTopChromeWebUI,
	"DeferredSpareRendererForTopChromeWebUI",
	base::FEATURE_DISABLED_BY_DEFAULT);
	// The delay time to create a new spare renderer since the previous spare
	// renderer is taken. This is not effective when
	// `delay_until_page_stopped_loading` is true.
	const base::FeatureParam<base::TimeDelta> kSpareRendererWarmupDelay{
	&kDeferredSpareRendererForTopChromeWebUI, "delay", base::Seconds(1)};
	// If true, a new spare renderer is not created until the last page stops
	// loading.
	const base::FeatureParam<bool> kSpareRendererWarmupDelayUntilPageStopsLoading{
	&kDeferredSpareRendererForTopChromeWebUI, "delay_until_page_stops_loading",
	false};

	// Destroy profiles when their last browser window is closed, instead of when
	// the browser exits.
	// On Lacros the feature is enabled only for secondary profiles, check the
	// implementation of `ProfileManager::ProfileInfo::FromUnownedProfile()`.
	BASE_FEATURE(kDestroyProfileOnBrowserClose,
	"DestroyProfileOnBrowserClose",
	#if BUILDFLAG(IS_LINUX) \|\| BUILDFLAG(IS_MAC) \|\| BUILDFLAG(IS_WIN) \|\| \
	BUILDFLAG(IS_CHROMEOS_LACROS)
	base::FEATURE_ENABLED_BY_DEFAULT);
	#else
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif

	// DestroyProfileOnBrowserClose only covers deleting regular (non-System)
	// Profiles. This flags lets us destroy the System Profile, as well.
	BASE_FEATURE(kDestroySystemProfiles,
	"DestroySystemProfiles",
	base::FEATURE_DISABLED_BY_DEFAULT);

	// Let the DevTools front-end query an AIDA endpoint for explanations and
	// insights regarding console (error) messages.
	BASE_FEATURE(kDevToolsConsoleInsights,
	"DevToolsConsoleInsights",
	base::FEATURE_DISABLED_BY_DEFAULT);
	const base::FeatureParam<std::string> kDevToolsConsoleInsightsAidaScope{
	&kDevToolsConsoleInsights, "aida_scope", /default/ ""};
	const base::FeatureParam<std::string> kDevToolsConsoleInsightsAidaEndpoint{
	&kDevToolsConsoleInsights, "aida_endpoint", /default/ ""};
	const base::FeatureParam<std::string> kDevToolsConsoleInsightsModelId{
	&kDevToolsConsoleInsights, "aida_model_id", /default/ ""};
	const base::FeatureParam<double> kDevToolsConsoleInsightsTemperature{
	&kDevToolsConsoleInsights, "aida_temperature", /default/ 0.2};
	const base::FeatureParam<bool> kDevToolsConsoleInsightsOptIn{
	&kDevToolsConsoleInsights, "opt_in", /default/ true};

	// Separate dogfood feature for DevTools console insights,
	// not restricted by enterprise policy or location.
	BASE_FEATURE(kDevToolsConsoleInsightsDogfood,
	"DevToolsConsoleInsightsDogfood",
	base::FEATURE_DISABLED_BY_DEFAULT);
	const base::FeatureParam<std::string> kDevToolsConsoleInsightsDogfoodAidaScope{
	&kDevToolsConsoleInsightsDogfood, "aida_scope", /default/ ""};
	const base::FeatureParam<std::string>
	kDevToolsConsoleInsightsDogfoodAidaEndpoint{
	&kDevToolsConsoleInsightsDogfood, "aida_endpoint", /default/ ""};
	const base::FeatureParam<std::string> kDevToolsConsoleInsightsDogfoodModelId{
	&kDevToolsConsoleInsightsDogfood, "aida_model_id", /default/ ""};
	const base::FeatureParam<double> kDevToolsConsoleInsightsDogfoodTemperature{
	&kDevToolsConsoleInsightsDogfood, "aida_temperature", /default/ 0.2};
	const base::FeatureParam<bool> kDevToolsConsoleInsightsDogfoodOptIn{
	&kDevToolsConsoleInsightsDogfood, "opt_in", /default/ true};

	// Whether DevTools shows the setting for console insights. The setting can be
	// shown in a disabled state, even if the feature itself is not available.
	BASE_FEATURE(kDevToolsConsoleInsightsSettingVisible,
	"DevToolsConsoleInsightsSettingVisible",
	base::FEATURE_DISABLED_BY_DEFAULT);
	const base::FeatureParam<std::string>
	kDevToolsConsoleInsightsSettingVisibleBlockedReason{
	&kDevToolsConsoleInsightsSettingVisible, "blocked_reason",
	/default/ ""};

	// Whether an infobar is shown when the process is shared.
	BASE_FEATURE(kDevToolsSharedProcessInfobar,
	"DevToolsSharedProcessInfobar",
	base::FEATURE_ENABLED_BY_DEFAULT);

	// Let DevTools front-end talk to the target of type "tab" rather than
	// "frame" when inspecting a WebContents.
	BASE_FEATURE(kDevToolsTabTarget,
	"DevToolsTabTarget",
	base::FEATURE_ENABLED_BY_DEFAULT);

	// Let DevTools front-end log extensive VisualElements-style UMA metrics for
	// impressions and interactions.
	BASE_FEATURE(kDevToolsVeLogging,
	"DevToolsVeLogging",
	base::FEATURE_ENABLED_BY_DEFAULT);

	#if BUILDFLAG(IS_CHROMEOS)
	// Enables being able to zoom a web page by double tapping in Chrome OS tablet
	// mode.
	BASE_FEATURE(kDoubleTapToZoomInTabletMode,
	"DoubleTapToZoomInTabletMode",
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif

	#if BUILDFLAG(IS_WIN)
	// When this feature is enabled, the DPAPI encryption provider will be
	// registered and enabled for encryption/decryption. This provider is
	// forwards/backwards compatible with OSCrypt sync.
	BASE_FEATURE(kEnableDPAPIEncryptionProvider,
	"EnableDPAPIEncryptionProvider",
	base::FEATURE_ENABLED_BY_DEFAULT);

	// When this feature is enabled, the App-Bound encryption provider is registered
	// with Chrome.
	BASE_FEATURE(kRegisterAppBoundEncryptionProvider,
	"RegisterAppBoundEncryptionProvider",
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif // BUILDFLAG(IS_WIN)

	// Enables usage of the FedCM API without third party cookies at the same time.
	BASE_FEATURE(kFedCmWithoutThirdPartyCookies,
	"FedCmWithoutThirdPartyCookies",
	base::FEATURE_DISABLED_BY_DEFAULT);

	// Enables showing the email of the flex org admin that setup CBCM in the
	// management disclosures.
	BASE_FEATURE(kFlexOrgManagementDisclosure,
	"FlexOrgManagementDisclosure",
	#if BUILDFLAG(IS_CHROMEOS)
	base::FEATURE_DISABLED_BY_DEFAULT);
	#else
	base::FEATURE_ENABLED_BY_DEFAULT);
	#endif // BUILDFLAG(IS_CHROMEOS)

	// Enables the Incoming Call Notifications scenario. When created by an
	// installed origin, an incoming call notification should have increased
	// priority, colored buttons, a ringtone, and a default "close" button.
	// Otherwise, if the origin is not installed, it should behave like the default
	// notifications, but with the added "Close" button. See
	// https://github.com/MicrosoftEdge/MSEdgeExplainers/blob/main/Notifications/notifications_actions_customization.md
	BASE_FEATURE(kIncomingCallNotifications,
	"IncomingCallNotifications",
	base::FEATURE_DISABLED_BY_DEFAULT);

	// Controls whether the static key pinning list can be updated via component
	// updater.
	BASE_FEATURE(kKeyPinningComponentUpdater,
	"KeyPinningComponentUpdater",
	base::FEATURE_ENABLED_BY_DEFAULT);

	BASE_FEATURE(kLargeFaviconFromGoogle,
	"LargeFaviconFromGoogle",
	base::FEATURE_DISABLED_BY_DEFAULT);
	const base::FeatureParam<int> kLargeFaviconFromGoogleSizeInDip{
	&kLargeFaviconFromGoogle, "favicon_size_in_dip", 128};

	#if BUILDFLAG(IS_WIN)
	// Enables locking the cookie database for profiles.
	// TODO(crbug.com/1430226): Remove after fully launched.
	BASE_FEATURE(kLockProfileCookieDatabase,
	"LockProfileCookieDatabase",
	base::FEATURE_ENABLED_BY_DEFAULT);
	#endif // BUILDFLAG(IS_WIN)

	#if !BUILDFLAG(IS_ANDROID)
	// Adds a "Snooze" action to mute notifications during screen sharing sessions.
	BASE_FEATURE(kMuteNotificationSnoozeAction,
	"MuteNotificationSnoozeAction",
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif

	// This feature enables monitoring of first-party network requests in order to
	// find possible violations. Example: A Chrome policy is set to disabled but the
	// network request controlled by that policy is observed.
	BASE_FEATURE(kNetworkAnnotationMonitoring,
	"NetworkAnnotationMonitoring",
	base::FEATURE_DISABLED_BY_DEFAULT);

	// This flag is used for enabling New Tab Page triggered prerendering. See
	// crbug.com/1462832 for more details of New Tab Page triggered prerendering.
	BASE_FEATURE(kNewTabPageTriggerForPrerender2,
	"NewTabPageTriggerForPrerender2",
	base::FEATURE_DISABLED_BY_DEFAULT);

	#if BUILDFLAG(IS_WIN)
	// Don't call the Win32 API PrefetchVirtualMemory when loading chrome.dll inside
	// non-browser processes. This is done by passing flags to these processes. This
	// prevents pulling the entirety of chrome.dll into physical memory (albeit only
	// pri-2 physical memory) under the assumption that during chrome execution,
	// portions of the DLL which are used will already be present, hopefully leading
	// to less needless memory consumption.
	BASE_FEATURE(kNoPreReadMainDll,
	"NoPreReadMainDll",
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif // BUILDFLAG(IS_WIN)

	#if BUILDFLAG(IS_ANDROID)
	// Adds an "Unsubscribe" action to web push notifications that allows stopping
	// notifications from a given origin with a single tap (with an option to undo).
	BASE_FEATURE(kNotificationOneTapUnsubscribe,
	"NotificationOneTapUnsubscribe",
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif

	// Enables omnibox trigger no state prefetch. Only one of
	// kOmniboxTriggerForPrerender2 or kOmniboxTriggerForNoStatePrefetch can be
	// enabled in the experiment. If both are enabled, only
	// kOmniboxTriggerForPrerender2 takes effect.
	// TODO(crbug.com/1267731): Remove this flag once the experiments are completed.
	BASE_FEATURE(kOmniboxTriggerForNoStatePrefetch,
	"OmniboxTriggerForNoStatePrefetch",
	base::FEATURE_DISABLED_BY_DEFAULT);

	// This flag is used for enabling Omnibox triggered prerendering. See
	// crbug.com/1166085 for more details of Omnibox triggered prerendering.
	BASE_FEATURE(kOmniboxTriggerForPrerender2,
	"OmniboxTriggerForPrerender2",
	base::FEATURE_ENABLED_BY_DEFAULT);

	#if BUILDFLAG(IS_CHROMEOS)
	// Enables AES keys support in the chrome.enterprise.platformKeys and
	// chrome.platformKeys APIs. The new operations include `sign`, `encrypt` and
	// `decrypt`. For additional details, see the proposal tracked in b/288880151.
	BASE_FEATURE(kPlatformKeysAesEncryption,
	"PlatformKeysAesEncryption",
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif // BUILDFLAG(IS_CHROMEOS)

	// Disables prerendering on the default search engine predictor. This is useful
	// in comparing the impact of the SupportSearchSuggestionForPrerender2 feature
	// during its rollout. Once that rollout is complete, this feature should be
	// removed and instead we should add a new long-term holdback to
	// PreloadingConfig.
	BASE_FEATURE(kPrerenderDSEHoldback,
	"PrerenderDSEHoldback",
	base::FEATURE_DISABLED_BY_DEFAULT);

	// Enables executing the browser commands sent by the NTP promos.
	BASE_FEATURE(kPromoBrowserCommands,
	"PromoBrowserCommands",
	base::FEATURE_ENABLED_BY_DEFAULT);

	// Parameter name for the promo browser command ID provided along with
	// kPromoBrowserCommands.
	// The value of this parameter should be parsable as an unsigned integer and
	// should map to one of the browser commands specified in:
	// ui/webui/resources/js/browser_command/browser_command.mojom
	const char kBrowserCommandIdParam[] = "BrowserCommandIdParam";

	#if BUILDFLAG(IS_CHROMEOS_ASH)
	// Enables reading and writing PWA notification permissions from quick settings
	// menu.
	BASE_FEATURE(kQuickSettingsPWANotifications,
	"QuickSettingsPWA",
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif

	#if !BUILDFLAG(IS_ANDROID)
	// Keeps accessibility enabled for WebContents as ReadAnything observes changes
	// to the active WebContents. This is a holdback study to evaluate the impact of
	// the new behavior, whereby the accessibility modes required by ReadyAnything
	// are cleared on a WebContents when ReadAnything loses interest in it.
	BASE_FEATURE(kReadAnythingPermanentAccessibility,
	"ReadAnythingPermanentAccessibility",
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif

	// When this feature is enabled, the network service will restart unsandboxed if
	// a previous attempt to launch it sandboxed failed.
	BASE_FEATURE(kRestartNetworkServiceUnsandboxedForFailedLaunch,
	"RestartNetworkServiceUnsandboxedForFailedLaunch",
	base::FEATURE_ENABLED_BY_DEFAULT);

	// Gates sandboxed iframe navigation toward external protocol behind any of:
	// - allow-top-navigation
	// - allow-top-navigation-to-custom-protocols
	// - allow-top-navigation-with-user-gesture (+ user gesture)
	// - allow-popups
	//
	// Motivation:
	// Developers are surprised that a sandboxed iframe can navigate and/or
	// redirect the user toward an external application.
	// General iframe navigation in sandboxed iframe are not blocked normally,
	// because they stay within the iframe. However they can be seen as a popup or
	// a top-level navigation when it leads to opening an external application. In
	// this case, it makes sense to extend the scope of sandbox flags, to block
	// malvertising.
	//
	// Implementation bug: https://crbug.com/1253379
	// I2S: https://groups.google.com/a/chromium.org/g/blink-dev/c/-t-f7I6VvOI
	//
	// Enabled in M103. Flag to be removed in M106
	BASE_FEATURE(kSandboxExternalProtocolBlocked,
	"SandboxExternalProtocolBlocked",
	base::FEATURE_ENABLED_BY_DEFAULT);
	// Enabled in M100. Flag to be removed in M106
	BASE_FEATURE(kSandboxExternalProtocolBlockedWarning,
	"SandboxExternalProtocolBlockedWarning",
	base::FEATURE_ENABLED_BY_DEFAULT);

	// This flag controls whether to trigger prerendering when the default search
	// engine suggests to prerender a search result.
	BASE_FEATURE(kSupportSearchSuggestionForPrerender2,
	"SupportSearchSuggestionForPrerender2",
	#if BUILDFLAG(IS_CHROMEOS_ASH) \|\| BUILDFLAG(IS_CHROMEOS_LACROS) \|\| \
	BUILDFLAG(IS_LINUX) \|\| BUILDFLAG(IS_MAC) \|\| BUILDFLAG(IS_WIN)
	base::FEATURE_ENABLED_BY_DEFAULT);
	#else
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif
	const base::FeatureParam<SearchPreloadShareableCacheType>::Option
	search_preload_shareable_cache_types[] = {
	{SearchPreloadShareableCacheType::kEnabled, "enabled"},
	{SearchPreloadShareableCacheType::kDisabled, "disabled"}};
	const base::FeatureParam<SearchPreloadShareableCacheType>
	kSearchPreloadShareableCacheTypeParam{
	&kSupportSearchSuggestionForPrerender2, "shareable_cache",
	SearchPreloadShareableCacheType::kEnabled,
	&search_preload_shareable_cache_types};

	// Enables migration of the network context data from `unsandboxed_data_path` to
	// `data_path`. See the explanation in network_context.mojom.
	BASE_FEATURE(kTriggerNetworkDataMigration,
	"TriggerNetworkDataMigration",
	#if BUILDFLAG(IS_WIN)
	base::FEATURE_ENABLED_BY_DEFAULT
	#else
	base::FEATURE_DISABLED_BY_DEFAULT
	#endif
	);

	#if BUILDFLAG(IS_CHROMEOS)
	// If enabled, a blue border is drawn around shared tabs on ChromeOS.
	// If disabled, the blue border is not used on ChromeOS.
	//
	// Motivation:
	// The blue border behavior used to cause problems on ChromeOS - see
	// crbug.com/1320262 for Ash (fixed) and crbug.com/1030925 for Lacros
	// (relatively old bug - we would like to observe whether it's still
	// there). This flag is introduced as means of disabling this feature in case
	// of possible future regressions.
	//
	// TODO(crbug.com/1251999): Remove this flag once we confirm that blue border
	// works fine on ChromeOS.
	//
	// b/279051234: We suspect the tab sharing blue border may cause a bad issue
	// on ChromeOS where a window can not be interacted at all. Disable the feature
	// on ChromeOS.
	BASE_FEATURE(kTabCaptureBlueBorderCrOS,
	"TabCaptureBlueBorderCrOS",
	base::FEATURE_DISABLED_BY_DEFAULT);
	#endif

	#if BUILDFLAG(IS_WIN)
	// When this feature is enabled, the network service will be passed an
	// OSCryptAsync crypto cookie delegate meaning that OSCryptAsync will be used
	// for cookie encryption.
	BASE_FEATURE(kUseOsCryptAsyncForCookieEncryption,
	"UseOsCryptAsyncForCookieEncryption",
	base::FEATURE_ENABLED_BY_DEFAULT);
	#endif // BUILDFLAG(IS_WIN)

	// Enables runtime detection of USB devices which provide a WebUSB landing page
	// descriptor.
	BASE_FEATURE(kWebUsbDeviceDetection,
	"WebUsbDeviceDetection",
	base::FEATURE_ENABLED_BY_DEFAULT);

	} // namespace features