sync initial

packages/flutter_mozilla_components/android/build.gradle

@@ -82,6 +82,8 @@ android {
 
 configurations.configureEach {
     exclude group: "org.mozilla.telemetry", module: "glean-native"
+    // Exclude standalone tink to avoid duplicate classes with tink-android
+    exclude group: "com.google.crypto.tink", module: "tink"
 }
 
 // Select the Glean from GeckoView.
@@ -114,6 +116,8 @@ dependencies {
     implementation "org.mozilla.components:browser-thumbnails:$mozillaComponentsVersion"
     implementation "org.mozilla.components:feature-addons:$mozillaComponentsVersion"
     implementation "org.mozilla.components:feature-app-links:$mozillaComponentsVersion"
+    implementation "org.mozilla.components:feature-accounts:$mozillaComponentsVersion"
+    implementation "org.mozilla.components:feature-accounts-push:$mozillaComponentsVersion"
     implementation "org.mozilla.components:feature-awesomebar:$mozillaComponentsVersion"
     implementation "org.mozilla.components:feature-customtabs:$mozillaComponentsVersion"
     implementation "org.mozilla.components:feature-downloads:$mozillaComponentsVersion"
@@ -122,6 +126,7 @@ dependencies {
     implementation "org.mozilla.components:feature-prompts:$mozillaComponentsVersion"
     implementation "org.mozilla.components:feature-session:$mozillaComponentsVersion"
     implementation "org.mozilla.components:feature-readerview:$mozillaComponentsVersion"
+    implementation "org.mozilla.components:feature-syncedtabs:$mozillaComponentsVersion"
     implementation "org.mozilla.components:feature-privatemode:$mozillaComponentsVersion"
     implementation "org.mozilla.components:feature-sitepermissions:$mozillaComponentsVersion"
     implementation "org.mozilla.components:feature-webcompat:$mozillaComponentsVersion"
@@ -131,6 +136,8 @@ dependencies {
     implementation "org.mozilla.components:feature-intent:$mozillaComponentsVersion"
     implementation "org.mozilla.components:ui-widgets:$mozillaComponentsVersion"
     implementation "org.mozilla.components:lib-publicsuffixlist:$mozillaComponentsVersion"
+    implementation "org.mozilla.components:service-firefox-accounts:$mozillaComponentsVersion"
+    implementation "org.mozilla.components:support-appservices:$mozillaComponentsVersion"
 
     implementation 'androidx.coordinatorlayout:coordinatorlayout:1.3.0'
     implementation 'androidx.swiperefreshlayout:swiperefreshlayout:1.2.0'

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/ActiveProfile.kt

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2024-2025 Fabian Freund.
+ *
+ * This file is part of WebLibre
+ * (see https://weblibre.eu).
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package eu.weblibre.flutter_mozilla_components
+
+import android.content.Context
+import java.io.File
+
+object ActiveProfile {
+    @Volatile
+    var prefix: String? = null
+
+    /** SharedPreference names used by mozilla-components FxA/sync that need profile isolation */
+    val FXA_SHARED_PREFERENCE_NAMES = setOf(
+        "fxaAppState",                  // FxA account state (SharedPrefAccountStorage)
+        "fxaStatePrefAC",               // Sentinel flag for SecureAbove22 account state presence
+        "fxaStateAC_kp_pre_m",          // SecureAbove22 encrypted account state (API < 23 fallback)
+        "fxaStateAC_kp_post_m",         // SecureAbove22 encrypted account state (API >= 23)
+        "fxa_abnormalities",            // Tracks FxA account abnormalities
+        "mozac_feature_accounts_push",  // Push subscription scope + verification state
+        "SyncAuthInfoCache",            // Cached sync auth tokens
+        "FxaDeviceSettingsCache",       // Cached device settings (ID, name, type)
+        "syncEngines",                  // Per-engine enabled/disabled state
+        "syncPrefs",                    // Last-synced timestamp + persisted sync state
+    )
+
+    /**
+     * Resolve the active profile prefix from disk.
+     * Called in Application.onCreate() to handle cold-start WorkManager scenarios.
+     */
+    fun resolveFromDisk(context: Context) {
+        val profileFile = File(context.filesDir, PwaConstants.CURRENT_PROFILE_FILE)
+        if (!profileFile.exists()) return
+        val uuid = profileFile.readText().trim().ifEmpty { return }
+        val relativePath = "${PwaConstants.PROFILES_DIR_NAME}/${PwaConstants.PROFILE_DIR_PREFIX}$uuid"
+        prefix = File(relativePath).name
+    }
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/BaseBrowserFragment.kt

@@ -37,6 +37,8 @@ import io.flutter.Log
 import mozilla.components.browser.state.state.WebExtensionState
 import mozilla.components.browser.thumbnails.BrowserThumbnails
 import mozilla.components.concept.engine.EngineView
+import mozilla.components.feature.accounts.FxaCapability
+import mozilla.components.feature.accounts.FxaWebChannelFeature
 import mozilla.components.feature.app.links.AppLinksFeature
 import mozilla.components.feature.downloads.DownloadsFeature
 import mozilla.components.feature.downloads.manager.FetchDownloadManager
@@ -85,6 +87,7 @@ abstract class BaseBrowserFragment : Fragment(), UserInteractionHandler, Activit
         ViewBoundFeatureWrapper<MediaSessionFullscreenFeature>()
 
     private val webAuthnFeature = ViewBoundFeatureWrapper<WebAuthnFeature>()
+    private val fxaWebChannelFeature = ViewBoundFeatureWrapper<FxaWebChannelFeature>()
 
     private var pictureInPictureFeature: PictureInPictureFeature? = null
 
@@ -450,6 +453,19 @@ abstract class BaseBrowserFragment : Fragment(), UserInteractionHandler, Activit
                 view = view
             )
 
+            fxaWebChannelFeature.set(
+                feature = FxaWebChannelFeature(
+                    customTabSessionId = sessionId,
+                    runtime = components.core.engine,
+                    store = components.core.store,
+                    accountManager = components.backgroundServices.accountManager,
+                    serverConfig = components.backgroundServices.serverConfig,
+                    fxaCapabilities = setOf(FxaCapability.CHOOSE_WHAT_TO_SYNC),
+                ),
+                owner = this,
+                view = view,
+            )
+
             readerViewFeature.set(
                 feature = ReaderViewIntegration(
                     profileContext,

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/Components.kt

@@ -9,6 +9,7 @@ package eu.weblibre.flutter_mozilla_components
 import android.content.Context
 import androidx.core.app.NotificationManagerCompat
 import eu.weblibre.flutter_mozilla_components.components.Core
+import eu.weblibre.flutter_mozilla_components.components.BackgroundServices
 import eu.weblibre.flutter_mozilla_components.components.Events
 import eu.weblibre.flutter_mozilla_components.components.Features
 import eu.weblibre.flutter_mozilla_components.components.Search
@@ -19,6 +20,7 @@ import eu.weblibre.flutter_mozilla_components.pigeons.BrowserExtensionEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.ContentBlocking
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoAddonEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoStateEvents
+import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSyncStateEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoTabContentEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.ReaderViewController
 import mozilla.components.concept.engine.EngineView
@@ -38,14 +40,38 @@ class Components(val profileApplicationContext: ProfileContext,
                  val logLevel: Log.Priority,
                  val contentBlocking: ContentBlocking,
                  val addonCollection: AddonCollection?,
+                 val fxaServerOverride: String?,
+                 val syncTokenServerOverride: String?,
                  val addonEvents: GeckoAddonEvents,
                  private val tabContentEvents: GeckoTabContentEvents,
-                 private val extensionEvents: BrowserExtensionEvents
+                 private val extensionEvents: BrowserExtensionEvents,
+                 private val syncStateEvents: GeckoSyncStateEvents?,
 ) {
     val core by lazy { Core(profileApplicationContext, this, flutterEvents, extensionEvents) }
+    val backgroundServices by lazy {
+        BackgroundServices(
+            context = profileApplicationContext,
+            browserStore = lazy { core.store },
+            historyStorage = core.lazyHistoryStorage,
+            bookmarkStorage = core.lazyBookmarksStorage,
+            remoteTabsStorage = core.lazyRemoteTabsStorage,
+            fxaServerOverride = fxaServerOverride,
+            syncTokenServerOverride = syncTokenServerOverride,
+            syncStateEvents = syncStateEvents,
+        )
+    }
     val events by lazy { Events(flutterEvents) }
     val useCases by lazy { UseCases(profileApplicationContext, core.engine, core.store, core.webAppShortcutManager) }
-    val services by lazy { Services(profileApplicationContext, core.store, useCases.tabsUseCases) }
+    val services by lazy {
+        Services(
+            profileApplicationContext,
+            core.store,
+            useCases.tabsUseCases,
+            backgroundServices.accountManager,
+            core.engine,
+            backgroundServices.serverConfig,
+        )
+    }
     val features by lazy { Features(core.engine, core.store, addonEvents, tabContentEvents) }
     val search by lazy { Search(profileApplicationContext, core, useCases) }
 
@@ -68,4 +94,4 @@ class Components(val profileApplicationContext: ProfileContext,
     val dateTimeProvider: DateTimeProvider by lazy { DefaultDateTimeProvider() }
 
     val downloadEstimator: DownloadEstimator by lazy { DownloadEstimator(dateTimeProvider = dateTimeProvider) }
-}
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/GlobalComponents.kt

@@ -15,6 +15,7 @@ import eu.weblibre.flutter_mozilla_components.pigeons.GeckoAddonEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSelectionActionEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoStateEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSuggestionEvents
+import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSyncStateEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoTabContentEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoViewportEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.QueryParameterStripping
@@ -26,6 +27,7 @@ import kotlinx.coroutines.DelicateCoroutinesApi
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.GlobalScope
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.runBlocking
 import mozilla.components.browser.storage.sync.GlobalPlacesDependencyProvider
 import mozilla.components.browser.state.action.CustomTabListAction
 import mozilla.components.browser.state.selector.findCustomTab
@@ -114,9 +116,12 @@ object GlobalComponents {
         addonEvents: GeckoAddonEvents,
         tabContentEvents: GeckoTabContentEvents,
         extensionEvents: BrowserExtensionEvents,
+        syncStateEvents: GeckoSyncStateEvents?,
         logLevel: Log.Priority,
         contentBlocking: ContentBlocking,
         addonCollection: AddonCollection?,
+        fxaServerOverride: String?,
+        syncTokenServerOverride: String?,
         mode: ComponentsMode = ComponentsMode.FULL,
     ) {
         Logger.debug("Creating new components")
@@ -137,18 +142,30 @@ object GlobalComponents {
             logLevel,
             contentBlocking,
             addonCollection,
+            fxaServerOverride,
+            syncTokenServerOverride,
             addonEvents,
             tabContentEvents,
             extensionEvents,
+            syncStateEvents,
         )
         _components = newComponents
         currentMode = mode
 
+        previousComponents?.let {
+            runCatching {
+                it.backgroundServices.accountManager.close()
+            }
+        }
+
         //newComponents.crashReporter.install(applicationContext)
 
         //Facts.registerProcessor(LogFactProcessor())
 
-        //RustHttpConfig.setClient(lazy { newComponents.core.client })
+        val megazordNetworkSetup = MegazordSetup.setupMegazordNetwork(
+            context = newComponents.profileApplicationContext,
+            client = lazy { newComponents.core.client },
+        )
 
         if (mode == ComponentsMode.FULL) {
             newComponents.core.engine.warmUp()
@@ -167,6 +184,12 @@ object GlobalComponents {
         }
 
         if (mode == ComponentsMode.FULL) {
+            if (!megazordNetworkSetup.isCompleted) {
+                runBlocking {
+                    megazordNetworkSetup.await()
+                }
+            }
+
             val restoreJob = restoreBrowserState(newComponents)
             if (previousCustomTabs.isNotEmpty()) {
                 restoreJob.invokeOnCompletion {
@@ -215,6 +238,12 @@ object GlobalComponents {
             GlobalScope.launch(Dispatchers.IO) {
                 newComponents.core.fileUploadsDirCleaner.cleanUploadsDirectory()
             }
+
+            // Eagerly initialize account manager so sync starts
+            newComponents.backgroundServices.accountManager
+
+            // Start FxA web channel feature for OAuth redirect handling
+            newComponents.services.fxaWebChannelFeature.start()
         } else {
             restorePreviousCustomTabs()
         }
@@ -256,9 +285,12 @@ object GlobalComponents {
             addonEvents = GeckoAddonEvents(messenger),
             tabContentEvents = GeckoTabContentEvents(messenger),
             extensionEvents = BrowserExtensionEvents(messenger),
+            syncStateEvents = null,
             logLevel = logLevel,
             contentBlocking = contentBlocking,
             addonCollection = null,
+            fxaServerOverride = null,
+            syncTokenServerOverride = null,
             mode = ComponentsMode.EXTERNAL,
         )
 

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/MegazordSetup.kt

@@ -0,0 +1,32 @@
+package eu.weblibre.flutter_mozilla_components
+
+import android.content.Context
+import android.content.pm.ApplicationInfo
+import kotlinx.coroutines.DelicateCoroutinesApi
+import kotlinx.coroutines.Deferred
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.async
+import mozilla.components.concept.fetch.Client
+import mozilla.components.support.AppServicesInitializer
+import mozilla.components.support.AppServicesInitializer.Config as AppServicesConfig
+import mozilla.components.support.rusthttp.RustHttpConfig
+
+object MegazordSetup {
+    fun setupEarlyMainProcess() {
+        AppServicesInitializer.init(AppServicesConfig(null))
+    }
+
+    @DelicateCoroutinesApi
+    fun setupMegazordNetwork(context: Context, client: Lazy<Client>): Deferred<Unit> =
+        GlobalScope.async(Dispatchers.IO) {
+            val isDebuggable =
+                (context.applicationInfo.flags and ApplicationInfo.FLAG_DEBUGGABLE) != 0
+
+            if (isDebuggable) {
+                RustHttpConfig.allowEmulatorLoopback()
+            }
+
+            RustHttpConfig.setClient(client)
+        }
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/ProfileContext.kt

@@ -43,6 +43,7 @@ class ProfileContext(private val base: Context, val relativePath: String) :
     }
 
     init {
+        ActiveProfile.prefix = profilePrefix
         customFilesDir.mkdirs()
         customNoBackupFilesDir.mkdirs()
         customObbDir.mkdirs()

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/activities/AuthCustomTabActivity.kt

@@ -0,0 +1,30 @@
+package eu.weblibre.flutter_mozilla_components.activities
+
+import mozilla.components.concept.sync.AccountObserver
+import mozilla.components.concept.sync.AuthType
+import mozilla.components.concept.sync.OAuthAccount
+import eu.weblibre.flutter_mozilla_components.GlobalComponents
+
+class AuthCustomTabActivity : ExternalAppBrowserActivity() {
+    private val accountStateObserver = object : AccountObserver {
+        override fun onAuthenticated(account: OAuthAccount, authType: AuthType) {
+            finish()
+        }
+    }
+
+    override fun onResume() {
+        super.onResume()
+        GlobalComponents.components
+            ?.backgroundServices
+            ?.accountManager
+            ?.register(accountStateObserver, this, true)
+    }
+
+    override fun onDestroy() {
+        GlobalComponents.components
+            ?.backgroundServices
+            ?.accountManager
+            ?.unregister(accountStateObserver)
+        super.onDestroy()
+    }
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/activities/AuthIntentReceiverActivity.kt

@@ -0,0 +1,54 @@
+package eu.weblibre.flutter_mozilla_components.activities
+
+import android.app.Activity
+import android.content.Intent
+import android.os.Bundle
+import android.util.Log
+import mozilla.components.feature.customtabs.CustomTabIntentProcessor
+import mozilla.components.feature.intent.ext.getSessionId
+import eu.weblibre.flutter_mozilla_components.GlobalComponents
+
+class AuthIntentReceiverActivity : Activity() {
+    companion object {
+        private const val TAG = "AuthIntentReceiver"
+    }
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        val sourceIntent = intent?.let { Intent(it) } ?: Intent()
+
+        if (GlobalComponents.components == null && !GlobalComponents.ensureExternalComponents(applicationContext)) {
+            finish()
+            return
+        }
+
+        val components = GlobalComponents.components
+        if (components == null) {
+            finish()
+            return
+        }
+
+        val processed = CustomTabIntentProcessor(
+            components.useCases.customTabsUseCases.add,
+            resources,
+            isPrivate = false,
+        ).process(sourceIntent)
+
+        if (processed) {
+            val sessionId = sourceIntent.getSessionId() ?: components.core.store.state.customTabs.lastOrNull()?.id
+            if (sessionId != null) {
+                val authIntent = ExternalAppBrowserActivity
+                    .createIntent(this, sessionId)
+                    .setClassName(this, AuthCustomTabActivity::class.java.name)
+                startActivity(authIntent)
+            } else {
+                Log.w(TAG, "Auth intent processed but no custom tab session id found")
+            }
+        } else {
+            Log.w(TAG, "Auth custom tab intent was not processed")
+        }
+
+        finish()
+    }
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/activities/ExternalAppBrowserActivity.kt

@@ -34,7 +34,7 @@ import mozilla.components.support.base.log.logger.Logger
  *
  * Uses an empty taskAffinity so Custom Tabs appear as a separate task from the main app.
  */
-class ExternalAppBrowserActivity : AppCompatActivity() {
+open class ExternalAppBrowserActivity : AppCompatActivity() {
     companion object {
         private const val TAG = "ExternalAppBrowserActivity"
 

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/api/GeckoBrowserApiImpl.kt

@@ -47,6 +47,8 @@ import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSessionApi
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoStateEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSuggestionApi
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSuggestionEvents
+import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSyncApi
+import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSyncStateEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoTabContentEvents
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoTabsApi
 import eu.weblibre.flutter_mozilla_components.pigeons.GeckoViewportApi
@@ -155,7 +157,9 @@ class GeckoBrowserApiImpl : GeckoBrowserApi {
         profileFolder: String,
         logLevel: LogLevel,
         contentBlocking: ContentBlocking,
-        addonCollection: AddonCollection?
+        addonCollection: AddonCollection?,
+        fxaServerOverride: String?,
+        syncTokenServerOverride: String?,
     ) {
         synchronized(this) {
             if (!isGeckoInitialized) {
@@ -170,7 +174,14 @@ class GeckoBrowserApiImpl : GeckoBrowserApi {
 
                 Log.addSink(PriorityAwareLogSink(level, geckoLogging))
 
-                setupGeckoEngine(profileFolder, level, contentBlocking, addonCollection)
+                setupGeckoEngine(
+                    profileFolder,
+                    level,
+                    contentBlocking,
+                    addonCollection,
+                    fxaServerOverride,
+                    syncTokenServerOverride,
+                )
                 isGeckoInitialized = true
             }
         }
@@ -190,7 +201,9 @@ class GeckoBrowserApiImpl : GeckoBrowserApi {
         profileFolder: String,
         logLevel: Log.Priority,
         contentBlocking: ContentBlocking,
-        addonCollection: AddonCollection?
+        addonCollection: AddonCollection?,
+        fxaServerOverride: String?,
+        syncTokenServerOverride: String?,
     ) {
         val profileApplicationContext = ProfileContext(_flutterPluginBinding.applicationContext, profileFolder)
 
@@ -220,6 +233,8 @@ class GeckoBrowserApiImpl : GeckoBrowserApi {
             GeckoSuggestionApiImpl(suggestionEvents)
         )
 
+        val syncStateEvents = GeckoSyncStateEvents(_flutterPluginBinding.binaryMessenger)
+
         GlobalComponents.setUp(
             profileApplicationContext,
             _flutterEvents,
@@ -228,9 +243,12 @@ class GeckoBrowserApiImpl : GeckoBrowserApi {
             addonEvents,
             tabContentEvents,
             extensionEvents,
+            syncStateEvents,
             logLevel,
             contentBlocking,
-            addonCollection
+            addonCollection,
+            fxaServerOverride,
+            syncTokenServerOverride,
         )
 
         val engineSettingsApiImpl = GeckoEngineSettingsApiImpl()
@@ -275,6 +293,7 @@ class GeckoBrowserApiImpl : GeckoBrowserApi {
         GeckoPublicSuffixListApi.setUp(_flutterPluginBinding.binaryMessenger, GeckoPublicSuffixListApiImpl(profileApplicationContext))
         GeckoTrackingProtectionApi.setUp(_flutterPluginBinding.binaryMessenger, GeckoTrackingProtectionApiImpl())
         GeckoAppLinksApi.setUp(_flutterPluginBinding.binaryMessenger, GeckoAppLinksApiImpl(profileApplicationContext))
+        GeckoSyncApi.setUp(_flutterPluginBinding.binaryMessenger, GeckoSyncApiImpl())
 
         // PWA API for web app installation and management
         GeckoPwaApi.setUp(_flutterPluginBinding.binaryMessenger, GeckoPwaApiImpl(profileApplicationContext))

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/api/GeckoSyncApiImpl.kt

@@ -0,0 +1,346 @@
+package eu.weblibre.flutter_mozilla_components.api
+
+import eu.weblibre.flutter_mozilla_components.GlobalComponents
+import eu.weblibre.flutter_mozilla_components.components.WebLibreFxAEntryPoint
+import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSyncApi
+import eu.weblibre.flutter_mozilla_components.pigeons.SyncAccountInfo
+import eu.weblibre.flutter_mozilla_components.pigeons.SyncDevice
+import eu.weblibre.flutter_mozilla_components.pigeons.SyncDeviceTabs
+import eu.weblibre.flutter_mozilla_components.pigeons.SyncEngineStatus
+import eu.weblibre.flutter_mozilla_components.pigeons.SyncEngineValue
+import eu.weblibre.flutter_mozilla_components.pigeons.SyncIncomingTab
+import eu.weblibre.flutter_mozilla_components.pigeons.SyncRemoteTab
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.launch
+import mozilla.components.concept.sync.DeviceCapability
+import mozilla.components.concept.sync.DeviceCommandOutgoing
+import mozilla.components.concept.sync.TabData
+import mozilla.components.service.fxa.SyncEngine
+import mozilla.components.service.fxa.manager.SCOPE_PROFILE
+import mozilla.components.service.fxa.manager.SCOPE_SYNC
+import mozilla.components.service.fxa.manager.SyncEnginesStorage
+import mozilla.components.service.fxa.sync.SyncReason
+import mozilla.components.service.fxa.sync.getLastSynced
+
+class GeckoSyncApiImpl : GeckoSyncApi {
+    companion object {
+        private val coroutineScope = CoroutineScope(Dispatchers.IO + SupervisorJob())
+    }
+
+    private val components by lazy {
+        requireNotNull(GlobalComponents.components) { "Components not initialized" }
+    }
+
+    override fun getAccountInfo(callback: (Result<SyncAccountInfo>) -> Unit) {
+        coroutineScope.launch {
+            try {
+                val accountManager = components.backgroundServices.accountManager
+                val account = accountManager.authenticatedAccount()
+                val needsReauth = accountManager.accountNeedsReauth()
+                val profile = account?.getProfile()
+                val engineStorage = SyncEnginesStorage(components.profileApplicationContext)
+                val engineStatus = engineStorage.getStatus()
+
+                callback(
+                    Result.success(
+                        SyncAccountInfo(
+                            authenticated = account != null && !needsReauth,
+                            syncing = accountManager.isSyncActive(),
+                            needsReauth = needsReauth,
+                            email = profile?.email,
+                            displayName = profile?.displayName,
+                            lastSyncedAt = getLastSynced(components.profileApplicationContext)
+                                .takeIf { it > 0L },
+                            engines = listOf(
+                                SyncEngineStatus(
+                                    engine = SyncEngineValue.HISTORY,
+                                    enabled = engineStatus[SyncEngine.History] ?: true,
+                                ),
+                                SyncEngineStatus(
+                                    engine = SyncEngineValue.BOOKMARKS,
+                                    enabled = engineStatus[SyncEngine.Bookmarks] ?: true,
+                                ),
+                                SyncEngineStatus(
+                                    engine = SyncEngineValue.TABS,
+                                    enabled = engineStatus[SyncEngine.Tabs] ?: true,
+                                ),
+                            ),
+                        ),
+                    ),
+                )
+            } catch (e: Exception) {
+                callback(Result.failure(e))
+            }
+        }
+    }
+
+    override fun beginAuthentication(callback: (Result<Unit>) -> Unit) {
+        coroutineScope.launch {
+            runCatching {
+                components.backgroundServices.awaitStarted()
+                components.services.accountsAuthFeature.beginAuthentication(
+                    context = components.profileApplicationContext,
+                    entrypoint = WebLibreFxAEntryPoint.Settings,
+                    scopes = setOf(SCOPE_PROFILE, SCOPE_SYNC),
+                )
+            }.fold(
+                onSuccess = { callback(Result.success(Unit)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun beginPairingAuthentication(
+        pairingUrl: String,
+        callback: (Result<Unit>) -> Unit,
+    ) {
+        coroutineScope.launch {
+            runCatching {
+                components.backgroundServices.awaitStarted()
+                components.services.accountsAuthFeature.beginPairingAuthentication(
+                    context = components.profileApplicationContext,
+                    pairingUrl = pairingUrl,
+                    entrypoint = WebLibreFxAEntryPoint.Settings,
+                    scopes = setOf(SCOPE_PROFILE, SCOPE_SYNC),
+                )
+            }.fold(
+                onSuccess = { callback(Result.success(Unit)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun logout(callback: (Result<Unit>) -> Unit) {
+        coroutineScope.launch {
+            runCatching {
+                components.backgroundServices.accountManager.logout()
+            }.fold(
+                onSuccess = { callback(Result.success(Unit)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun syncNow(callback: (Result<Unit>) -> Unit) {
+        coroutineScope.launch {
+            runCatching {
+                components.backgroundServices.accountManager.syncNow(SyncReason.User)
+            }.fold(
+                onSuccess = { callback(Result.success(Unit)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun setEngineEnabled(
+        engine: SyncEngineValue,
+        enabled: Boolean,
+        callback: (Result<Unit>) -> Unit,
+    ) {
+        coroutineScope.launch {
+            runCatching {
+                val storage = SyncEnginesStorage(components.profileApplicationContext)
+                val mapped = when (engine) {
+                    SyncEngineValue.HISTORY -> SyncEngine.History
+                    SyncEngineValue.BOOKMARKS -> SyncEngine.Bookmarks
+                    SyncEngineValue.TABS -> SyncEngine.Tabs
+                }
+
+                storage.setStatus(mapped, enabled)
+                components.backgroundServices.accountManager.syncNow(SyncReason.EngineChange)
+            }.fold(
+                onSuccess = { callback(Result.success(Unit)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun getSyncedTabs(callback: (Result<List<SyncDeviceTabs>>) -> Unit) {
+        coroutineScope.launch {
+            runCatching {
+                val deviceNames = loadDeviceDisplayNames()
+                components.core.remoteTabsStorage.getAll().entries.mapNotNull { (client, tabs) ->
+                    val deviceName = deviceNames[client.id] ?: return@mapNotNull null
+                    SyncDeviceTabs(
+                        deviceId = client.id,
+                        deviceName = deviceName,
+                        tabs = tabs.map { tab ->
+                            val active = tab.active()
+                            SyncRemoteTab(
+                                title = active.title,
+                                url = active.url,
+                                iconUrl = active.iconUrl,
+                                lastUsed = tab.lastUsed,
+                                inactive = tab.inactive,
+                            )
+                        }.sortedByDescending { it.lastUsed },
+                    )
+                }.sortedBy { it.deviceName.lowercase() }
+            }.fold(
+                onSuccess = { callback(Result.success(it)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun getDevices(callback: (Result<List<SyncDevice>>) -> Unit) {
+        coroutineScope.launch {
+            runCatching {
+                components.backgroundServices.awaitStarted()
+                val account = components.backgroundServices.accountManager.authenticatedAccount()
+                    ?: return@runCatching emptyList()
+
+                val constellation = account.deviceConstellation()
+                constellation.refreshDevices()
+                val state = constellation.state()
+                val currentDevice = state?.currentDevice
+                val otherDevices = state?.otherDevices.orEmpty()
+
+                (listOfNotNull(currentDevice) + otherDevices).map { device ->
+                    SyncDevice(
+                        deviceId = device.id,
+                        displayName = device.displayName,
+                        isCurrentDevice = device.isCurrentDevice,
+                        canSendTab = device.capabilities.contains(DeviceCapability.SEND_TAB),
+                    )
+                }.sortedBy { it.displayName.lowercase() }
+            }.fold(
+                onSuccess = { callback(Result.success(it)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun sendTabToDevice(
+        deviceId: String,
+        title: String,
+        url: String,
+        callback: (Result<Boolean>) -> Unit,
+    ) {
+        coroutineScope.launch {
+            runCatching {
+                components.backgroundServices.awaitStarted()
+                val account = components.backgroundServices.accountManager.authenticatedAccount()
+                    ?: return@runCatching false
+
+                val constellation = account.deviceConstellation()
+                constellation.refreshDevices()
+                val state = constellation.state()
+                val target = state?.otherDevices?.firstOrNull {
+                    it.id == deviceId && it.capabilities.contains(DeviceCapability.SEND_TAB)
+                } ?: return@runCatching false
+
+                constellation.sendCommandToDevice(
+                    target.id,
+                    DeviceCommandOutgoing.SendTab(
+                        title = title,
+                        url = url,
+                    ),
+                )
+            }.fold(
+                onSuccess = { callback(Result.success(it)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun refreshDevices(callback: (Result<Unit>) -> Unit) {
+        coroutineScope.launch {
+            runCatching {
+                components.backgroundServices.awaitStarted()
+                val account = components.backgroundServices.accountManager.authenticatedAccount()
+                    ?: return@runCatching
+
+                account.deviceConstellation().refreshDevices()
+            }.fold(
+                onSuccess = { callback(Result.success(Unit)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun pollDeviceCommands(callback: (Result<Unit>) -> Unit) {
+        coroutineScope.launch {
+            runCatching {
+                components.backgroundServices.awaitStarted()
+                val account = components.backgroundServices.accountManager.authenticatedAccount()
+                    ?: return@runCatching
+
+                account.deviceConstellation().pollForCommands()
+            }.fold(
+                onSuccess = { callback(Result.success(Unit)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun drainIncomingTabs(callback: (Result<List<SyncIncomingTab>>) -> Unit) {
+        coroutineScope.launch {
+            runCatching {
+                components.backgroundServices.drainIncomingTabs().map {
+                    SyncIncomingTab(
+                        title = it.title,
+                        url = it.url,
+                        fromDeviceId = it.fromDeviceId,
+                        fromDeviceName = it.fromDeviceName,
+                    )
+                }
+            }.fold(
+                onSuccess = { callback(Result.success(it)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun getDeviceName(callback: (Result<String?>) -> Unit) {
+        coroutineScope.launch {
+            runCatching {
+                components.backgroundServices.awaitStarted()
+                val account = components.backgroundServices.accountManager.authenticatedAccount()
+                    ?: return@runCatching null
+
+                val constellation = account.deviceConstellation()
+                constellation.refreshDevices()
+                constellation.state()?.currentDevice?.displayName
+            }.fold(
+                onSuccess = { callback(Result.success(it)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    override fun setDeviceName(newName: String, callback: (Result<Boolean>) -> Unit) {
+        coroutineScope.launch {
+            runCatching {
+                val trimmed = newName.trim()
+                if (trimmed.isEmpty()) {
+                    return@runCatching false
+                }
+
+                components.backgroundServices.awaitStarted()
+                val account = components.backgroundServices.accountManager.authenticatedAccount()
+                    ?: return@runCatching false
+
+                account.deviceConstellation()
+                    .setDeviceName(trimmed, components.profileApplicationContext)
+            }.fold(
+                onSuccess = { callback(Result.success(it)) },
+                onFailure = { callback(Result.failure(it)) },
+            )
+        }
+    }
+
+    private suspend fun loadDeviceDisplayNames(): Map<String, String> {
+        components.backgroundServices.awaitStarted()
+        val account = components.backgroundServices.accountManager.authenticatedAccount()
+            ?: return emptyMap()
+
+        val constellation = account.deviceConstellation()
+        constellation.refreshDevices()
+        val state = constellation.state() ?: return emptyMap()
+        val devices = listOfNotNull(state.currentDevice) + state.otherDevices
+        return devices.associate { it.id to it.displayName }
+    }
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/components/BackgroundServices.kt

@@ -0,0 +1,315 @@
+package eu.weblibre.flutter_mozilla_components.components
+
+import android.content.Context
+import android.content.pm.ApplicationInfo
+import android.os.Build
+import kotlinx.coroutines.CompletableDeferred
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.MainScope
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withTimeout
+import mozilla.components.concept.sync.AccountObserver
+import mozilla.components.concept.sync.AuthType
+import mozilla.components.concept.sync.Device
+import mozilla.components.concept.sync.OAuthAccount
+import mozilla.components.concept.sync.Profile
+import mozilla.components.concept.sync.TabData
+import mozilla.components.browser.storage.sync.PlacesBookmarksStorage
+import mozilla.components.browser.storage.sync.PlacesHistoryStorage
+import mozilla.components.browser.storage.sync.RemoteTabsStorage
+import mozilla.components.concept.sync.DeviceConfig
+import mozilla.components.concept.sync.DeviceCapability
+import mozilla.components.concept.sync.DeviceType
+import mozilla.components.feature.accounts.push.SendTabFeature
+import mozilla.components.feature.syncedtabs.storage.SyncedTabsStorage
+import mozilla.components.service.fxa.PeriodicSyncConfig
+import mozilla.components.service.fxa.ServerConfig
+import mozilla.components.service.fxa.SyncConfig
+import mozilla.components.service.fxa.SyncEngine
+import mozilla.components.service.fxa.manager.FxaAccountManager
+import mozilla.components.service.fxa.manager.SCOPE_SESSION
+import mozilla.components.service.fxa.manager.SCOPE_SYNC
+import mozilla.components.service.fxa.manager.SyncEnginesStorage
+import mozilla.components.service.fxa.sync.GlobalSyncableStoreProvider
+import mozilla.components.service.fxa.sync.SyncReason
+import mozilla.components.service.fxa.sync.SyncStatusObserver
+import mozilla.components.service.fxa.sync.getLastSynced
+import eu.weblibre.flutter_mozilla_components.pigeons.GeckoSyncStateEvents
+import eu.weblibre.flutter_mozilla_components.pigeons.SyncAccountInfo
+import eu.weblibre.flutter_mozilla_components.pigeons.SyncEngineStatus
+import eu.weblibre.flutter_mozilla_components.pigeons.SyncEngineValue
+import eu.weblibre.flutter_mozilla_components.sync.SyncedTabsIntegration
+import mozilla.components.browser.state.store.BrowserStore
+import androidx.lifecycle.ProcessLifecycleOwner
+import org.mozilla.gecko.util.ThreadUtils.runOnUiThread
+import java.util.concurrent.atomic.AtomicBoolean
+import java.util.concurrent.atomic.AtomicLong
+import java.util.concurrent.TimeUnit
+
+class BackgroundServices(
+    private val context: Context,
+    private val browserStore: Lazy<BrowserStore>,
+    private val historyStorage: Lazy<PlacesHistoryStorage>,
+    private val bookmarkStorage: Lazy<PlacesBookmarksStorage>,
+    private val remoteTabsStorage: Lazy<RemoteTabsStorage>,
+    private val fxaServerOverride: String?,
+    private val syncTokenServerOverride: String?,
+    private val syncStateEvents: GeckoSyncStateEvents?,
+) {
+    companion object {
+        private const val MIN_STARTUP_SYNC_INTERVAL_MS = 15 * 60 * 1000L
+        private val MAX_ACTIVE_TIME_MS = TimeUnit.DAYS.toMillis(14L)
+    }
+
+    data class IncomingTab(
+        val title: String,
+        val url: String,
+        val fromDeviceId: String?,
+        val fromDeviceName: String?,
+    )
+
+    private val incomingTabsLock = Any()
+    private val incomingTabsQueue = ArrayDeque<IncomingTab>()
+    private val startedSignal = CompletableDeferred<Unit>()
+    private val authStateScope = CoroutineScope(SupervisorJob() + Dispatchers.Default)
+    private val authStateLock = Any()
+    private var lastAuthState: SyncAccountInfo? = null
+    private val isDebuggable =
+        (context.applicationInfo.flags and ApplicationInfo.FLAG_DEBUGGABLE) != 0
+
+    private val supportedEngines = setOf(
+        SyncEngine.History,
+        SyncEngine.Bookmarks,
+        SyncEngine.Tabs,
+    )
+
+    private val syncConfig = SyncConfig(
+        supportedEngines,
+        periodicSyncConfig = PeriodicSyncConfig(periodMinutes = 240),
+    )
+
+    val syncedTabsStorage by lazy {
+        SyncedTabsStorage(
+            accountManager,
+            browserStore.value,
+            remoteTabsStorage.value,
+            MAX_ACTIVE_TIME_MS,
+        )
+    }
+
+    val serverConfig: ServerConfig = FxaServer.config(
+        context = context,
+        serverOverride = fxaServerOverride,
+        tokenServerOverride = syncTokenServerOverride,
+    )
+
+    private val deviceConfig = DeviceConfig(
+        name = "WebLibre ${Build.MANUFACTURER} ${Build.MODEL}",
+        type = DeviceType.MOBILE,
+        capabilities = setOf(DeviceCapability.SEND_TAB, DeviceCapability.CLOSE_TABS),
+        secureStateAtRest = true,
+    )
+
+    init {
+        GlobalSyncableStoreProvider.configureStore(SyncEngine.History to historyStorage)
+        GlobalSyncableStoreProvider.configureStore(SyncEngine.Bookmarks to bookmarkStorage)
+        GlobalSyncableStoreProvider.configureStore(SyncEngine.Tabs to remoteTabsStorage)
+    }
+
+    private val sequenceCounter = AtomicLong(0)
+    private val syncedTabsIntegrationLaunched = AtomicBoolean(false)
+
+    private fun dispatchAuthState(account: OAuthAccount?, needsReauth: Boolean = false) {
+        val events = syncStateEvents ?: return
+        authStateScope.launch {
+            val profile = account?.getProfile()
+            val engineStorage = SyncEnginesStorage(context)
+            val engineStatus = engineStorage.getStatus()
+
+            val info = SyncAccountInfo(
+                authenticated = account != null && !needsReauth,
+                syncing = accountManager.isSyncActive(),
+                needsReauth = needsReauth,
+                email = profile?.email,
+                displayName = profile?.displayName,
+                lastSyncedAt = getLastSynced(context).takeIf { it > 0L },
+                engines = listOf(
+                    SyncEngineStatus(
+                        engine = SyncEngineValue.HISTORY,
+                        enabled = engineStatus[SyncEngine.History] ?: true,
+                    ),
+                    SyncEngineStatus(
+                        engine = SyncEngineValue.BOOKMARKS,
+                        enabled = engineStatus[SyncEngine.Bookmarks] ?: true,
+                    ),
+                    SyncEngineStatus(
+                        engine = SyncEngineValue.TABS,
+                        enabled = engineStatus[SyncEngine.Tabs] ?: true,
+                    ),
+                ),
+            )
+
+            val shouldEmit = synchronized(authStateLock) {
+                if (lastAuthState == info) {
+                    false
+                } else {
+                    lastAuthState = info
+                    true
+                }
+            }
+
+            if (!shouldEmit) {
+                return@launch
+            }
+
+            runOnUiThread {
+                events.onAuthStateChanged(sequenceCounter.incrementAndGet(), info) { _ -> }
+            }
+        }
+    }
+
+    val accountManager: FxaAccountManager by lazy {
+        FxaAccountManager(
+            context = context,
+            serverConfig = serverConfig,
+            deviceConfig = deviceConfig,
+            syncConfig = syncConfig,
+            applicationScopes = setOf(SCOPE_SYNC, SCOPE_SESSION),
+            crashReporter = null,
+        ).also { accountManager ->
+            SendTabFeature(accountManager) { device: Device?, tabs: List<TabData> ->
+                synchronized(incomingTabsLock) {
+                    tabs.forEach { tab ->
+                        incomingTabsQueue.addLast(
+                            IncomingTab(
+                                title = tab.title,
+                                url = tab.url,
+                                fromDeviceId = device?.id,
+                                fromDeviceName = device?.displayName,
+                            ),
+                        )
+                    }
+                }
+            }
+
+            accountManager.register(object : AccountObserver {
+                override fun onReady(authenticatedAccount: OAuthAccount?) {
+                    if (!startedSignal.isCompleted) {
+                        startedSignal.complete(Unit)
+                    }
+                }
+
+                override fun onAuthenticated(account: OAuthAccount, authType: AuthType) {
+                    dispatchAuthState(account)
+                }
+
+                override fun onAuthenticationProblems() {
+                    dispatchAuthState(accountManager.authenticatedAccount(), needsReauth = true)
+                }
+
+                override fun onLoggedOut() {
+                    dispatchAuthState(null)
+                }
+
+                override fun onProfileUpdated(profile: Profile) {
+                    dispatchAuthState(accountManager.authenticatedAccount())
+                }
+
+                override fun onFlowError(error: mozilla.components.concept.sync.AuthFlowError) {
+                    dispatchAuthState(accountManager.authenticatedAccount(), needsReauth = true)
+                }
+            })
+
+            accountManager.registerForSyncEvents(object : SyncStatusObserver {
+                override fun onStarted() {
+                    val events = syncStateEvents ?: return
+                    dispatchAuthState(accountManager.authenticatedAccount())
+                    runOnUiThread {
+                        events.onSyncStarted(sequenceCounter.incrementAndGet()) { _ -> }
+                    }
+                }
+
+                override fun onIdle() {
+                    val events = syncStateEvents ?: return
+                    dispatchAuthState(accountManager.authenticatedAccount())
+                    runOnUiThread {
+                        events.onSyncCompleted(sequenceCounter.incrementAndGet()) { _ -> }
+                    }
+                }
+
+                override fun onError(error: Exception?) {
+                    val events = syncStateEvents ?: return
+                    dispatchAuthState(accountManager.authenticatedAccount())
+                    runOnUiThread {
+                        events.onSyncError(
+                            sequenceCounter.incrementAndGet(),
+                            error?.message,
+                        ) { _ -> }
+                    }
+                }
+            }, owner = ProcessLifecycleOwner.get(), autoPause = false)
+
+            MainScope().launch {
+                runCatching {
+                    accountManager.start()
+                }.fold(
+                    onSuccess = {},
+                    onFailure = { error ->
+                        val isDuplicateInitialize = error.message
+                            ?.contains("Initialize already sent", ignoreCase = true)
+                            ?: false
+
+                        if (isDuplicateInitialize) {
+                            return@fold
+                        }
+
+                        if (!startedSignal.isCompleted) {
+                            startedSignal.completeExceptionally(error)
+                        }
+                        throw error
+                    },
+                )
+                if (accountManager.authenticatedAccount() != null && shouldSyncOnStartup()) {
+                    accountManager.syncNow(SyncReason.Startup)
+                }
+            }
+        }
+    }
+
+    suspend fun awaitStarted() {
+        accountManager
+        launchSyncedTabsIntegrationIfNeeded()
+        withTimeout(10_000) {
+            startedSignal.await()
+        }
+    }
+
+    private fun launchSyncedTabsIntegrationIfNeeded() {
+        if (syncedTabsIntegrationLaunched.compareAndSet(false, true)) {
+            SyncedTabsIntegration(accountManager, syncedTabsStorage).launch()
+        }
+    }
+
+    private fun shouldSyncOnStartup(): Boolean {
+        val lastSynced = getLastSynced(context)
+        if (lastSynced <= 0L) {
+            return true
+        }
+
+        return (System.currentTimeMillis() - lastSynced) >= MIN_STARTUP_SYNC_INTERVAL_MS
+    }
+
+    fun drainIncomingTabs(): List<IncomingTab> {
+        synchronized(incomingTabsLock) {
+            if (incomingTabsQueue.isEmpty()) {
+                return emptyList()
+            }
+
+            val values = incomingTabsQueue.toList()
+            incomingTabsQueue.clear()
+            return values
+        }
+    }
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/components/Core.kt

@@ -33,6 +33,7 @@ import mozilla.components.browser.state.engine.middleware.SessionPrioritizationM
 import mozilla.components.browser.state.store.BrowserStore
 import mozilla.components.browser.storage.sync.PlacesBookmarksStorage
 import mozilla.components.browser.storage.sync.PlacesHistoryStorage
+import mozilla.components.browser.storage.sync.RemoteTabsStorage
 import mozilla.components.browser.thumbnails.ThumbnailsMiddleware
 import mozilla.components.browser.thumbnails.storage.ThumbnailStorage
 import mozilla.components.concept.engine.DefaultSettings
@@ -62,8 +63,11 @@ import mozilla.components.feature.session.middleware.LastAccessMiddleware
 import mozilla.components.feature.session.middleware.undo.UndoMiddleware
 import mozilla.components.feature.sitepermissions.OnDiskSitePermissionsStorage
 import mozilla.components.feature.webnotifications.WebNotificationFeature
+import mozilla.components.concept.base.crash.Breadcrumb
+import mozilla.components.concept.base.crash.CrashReporting
 import mozilla.components.support.base.worker.Frequency
 import org.mozilla.geckoview.GeckoRuntime
+import kotlinx.coroutines.Job
 import java.util.concurrent.TimeUnit
 
 private const val AMO_COLLECTION_MAX_CACHE_AGE = 24 * 60L
@@ -74,6 +78,12 @@ class Core(
     private val flutterEvents: GeckoStateEvents,
     private val extensionEvents: BrowserExtensionEvents
 ) {
+    private val noOpCrashReporter = object : CrashReporting {
+        override fun submitCaughtException(throwable: Throwable): Job = Job()
+
+        override fun recordCrashBreadcrumb(breadcrumb: Breadcrumb) = Unit
+    }
+
     val prefs by lazy {
         PreferenceManager.getDefaultSharedPreferences(context)
     }
@@ -251,12 +261,14 @@ class Core(
      */
     val lazyHistoryStorage = lazy { PlacesHistoryStorage(context) }
     val lazyBookmarksStorage = lazy { PlacesBookmarksStorage(context) }
+    val lazyRemoteTabsStorage = lazy { RemoteTabsStorage(context, noOpCrashReporter) }
 
     /**
      * A convenience accessor to the [PlacesHistoryStorage].
      */
     val historyStorage by lazy { lazyHistoryStorage.value }
     val bookmarksStorage by lazy { lazyBookmarksStorage.value }
+    val remoteTabsStorage by lazy { lazyRemoteTabsStorage.value }
 
     val permissionStorage by lazy { PermissionStorage(geckoSitePermissionsStorage) }
 

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/components/FxaServer.kt

@@ -0,0 +1,30 @@
+package eu.weblibre.flutter_mozilla_components.components
+
+import android.content.Context
+import mozilla.appservices.fxaclient.FxaServer as AppServicesFxaServer
+import mozilla.components.service.fxa.ServerConfig
+
+object FxaServer {
+    private const val CLIENT_ID = "a2270f727f45f648"
+    const val REDIRECT_URL = "urn:ietf:wg:oauth:2.0:oob:oauth-redirect-webchannel"
+
+    fun config(
+        context: Context,
+        serverOverride: String?,
+        tokenServerOverride: String?
+    ): ServerConfig {
+        val effectiveServerOverride = serverOverride?.trim().orEmpty()
+        val effectiveTokenOverride = tokenServerOverride?.trim().takeUnless { it.isNullOrEmpty() }
+
+        return if (effectiveServerOverride.isEmpty()) {
+            ServerConfig(AppServicesFxaServer.Release, CLIENT_ID, REDIRECT_URL, effectiveTokenOverride)
+        } else {
+            ServerConfig(
+                AppServicesFxaServer.Custom(effectiveServerOverride),
+                CLIENT_ID,
+                REDIRECT_URL,
+                effectiveTokenOverride,
+            )
+        }
+    }
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/components/Services.kt

@@ -5,13 +5,26 @@
 package eu.weblibre.flutter_mozilla_components.components
 
 import android.content.Context
+import android.content.Intent
+import androidx.browser.customtabs.CustomTabsIntent
+import androidx.core.net.toUri
 import androidx.preference.PreferenceManager
 import eu.weblibre.flutter_mozilla_components.GlobalComponents
 import eu.weblibre.flutter_mozilla_components.R
+import eu.weblibre.flutter_mozilla_components.activities.AuthIntentReceiverActivity
 import eu.weblibre.flutter_mozilla_components.ext.getPreferenceKey
 import mozilla.components.browser.state.store.BrowserStore
+import mozilla.components.concept.engine.Engine
+import mozilla.components.feature.accounts.FirefoxAccountsAuthFeature
+import mozilla.components.feature.accounts.FxaCapability
+import mozilla.components.feature.accounts.FxaWebChannelFeature
 import mozilla.components.feature.app.links.AppLinksInterceptor
 import mozilla.components.feature.tabs.TabsUseCases
+import mozilla.components.service.fxa.ServerConfig
+import mozilla.components.service.fxa.manager.FxaAccountManager
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
 
 /**
  * Component group which encapsulates foreground-friendly services.
@@ -20,9 +33,39 @@ class Services(
     private val context: Context,
     private val store: BrowserStore,
     private val tabsUseCases: TabsUseCases,
+    accountManager: FxaAccountManager,
+    private val engine: Engine,
+    private val serverConfig: ServerConfig,
 ) {
     private val prefs = PreferenceManager.getDefaultSharedPreferences(context)
 
+    val accountsAuthFeature by lazy {
+        FirefoxAccountsAuthFeature(accountManager, FxaServer.REDIRECT_URL) { _, authUrl ->
+            CoroutineScope(Dispatchers.Main).launch {
+                val intent = CustomTabsIntent.Builder()
+                    .setInstantAppsEnabled(false)
+                    .build()
+                    .intent
+                    .setData(authUrl.toUri())
+                    .setClassName(context, AuthIntentReceiverActivity::class.java.name)
+                    .setPackage(context.packageName)
+                    .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
+                context.startActivity(intent)
+            }
+        }
+    }
+
+    val fxaWebChannelFeature by lazy {
+        FxaWebChannelFeature(
+            customTabSessionId = null,
+            runtime = engine,
+            store = store,
+            accountManager = accountManager,
+            serverConfig = serverConfig,
+            fxaCapabilities = setOf(FxaCapability.CHOOSE_WHAT_TO_SYNC),
+        )
+    }
+
     val appLinksInterceptor by lazy {
         AppLinksInterceptor(
             context = context,

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/components/WebLibreFxAEntryPoint.kt

@@ -0,0 +1,7 @@
+package eu.weblibre.flutter_mozilla_components.components
+
+import mozilla.components.concept.sync.FxAEntryPoint
+
+enum class WebLibreFxAEntryPoint(override val entryName: String) : FxAEntryPoint {
+    Settings("settings"),
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/interceptor/AppRequestInterceptor.kt

@@ -42,6 +42,19 @@ class AppRequestInterceptor(private val context: Context) : RequestInterceptor {
             return null
         }
 
+        components.services.accountsAuthFeature.interceptor.onLoadRequest(
+            engineSession,
+            uri,
+            lastUri,
+            hasUserGesture,
+            isSameDomain,
+            isRedirect,
+            isDirectNavigation,
+            isSubframeRequest,
+        )?.let {
+            return it
+        }
+
         return components.services.appLinksInterceptor.onLoadRequest(
             engineSession,
             uri,
@@ -64,4 +77,4 @@ class AppRequestInterceptor(private val context: Context) : RequestInterceptor {
     }
 
     override fun interceptsAppInitiatedRequests() = true
-}
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/sync/SyncedTabsIntegration.kt

@@ -0,0 +1,35 @@
+package eu.weblibre.flutter_mozilla_components.sync
+
+import mozilla.components.concept.sync.AccountObserver
+import mozilla.components.concept.sync.AuthType
+import mozilla.components.concept.sync.OAuthAccount
+import mozilla.components.feature.syncedtabs.storage.SyncedTabsStorage
+import mozilla.components.service.fxa.manager.FxaAccountManager
+
+/**
+ * Starts and stops SyncedTabsStorage based on the authentication state.
+ */
+class SyncedTabsIntegration(
+    private val accountManager: FxaAccountManager,
+    private val syncedTabsStorage: SyncedTabsStorage,
+) {
+    fun launch() {
+        accountManager.register(SyncedTabsAccountObserver(syncedTabsStorage))
+
+        if (accountManager.authenticatedAccount() != null) {
+            syncedTabsStorage.start()
+        }
+    }
+}
+
+internal class SyncedTabsAccountObserver(
+    private val syncedTabsStorage: SyncedTabsStorage,
+) : AccountObserver {
+    override fun onAuthenticated(account: OAuthAccount, authType: AuthType) {
+        syncedTabsStorage.start()
+    }
+
+    override fun onLoggedOut() {
+        syncedTabsStorage.stop()
+    }
+}