improve shutdown routine

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

@@ -31,9 +31,8 @@ import org.mozilla.geckoview.GeckoRuntimeSettings
 object EngineProvider {
     private var runtime: GeckoRuntime? = null
 
-    private val components by lazy {
-        requireNotNull(GlobalComponents.components) { "Components not initialized" }
-    }
+    private val components: Components
+        get() = requireNotNull(GlobalComponents.components) { "Components not initialized" }
 
     @Synchronized
     fun getOrCreateRuntime(context: Context): GeckoRuntime {
@@ -148,4 +147,13 @@ object EngineProvider {
         val runtime = getOrCreateRuntime(context)
         return GeckoViewFetchClient(context, runtime)
     }
+
+    @Synchronized
+    fun shutdown() {
+        runtime?.let {
+            Logger.debug("Shutting down GeckoRuntime")
+            it.shutdown()
+            runtime = null
+        }
+    }
 }

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

@@ -12,6 +12,7 @@ import android.view.View
 import androidx.fragment.app.FragmentActivity
 import eu.weblibre.flutter_mozilla_components.BrowserFragment
 import eu.weblibre.flutter_mozilla_components.GeckoViewFactory
+import eu.weblibre.flutter_mozilla_components.EngineProvider
 import eu.weblibre.flutter_mozilla_components.GlobalComponents
 import eu.weblibre.flutter_mozilla_components.ProfileContext
 import eu.weblibre.flutter_mozilla_components.activities.ExternalAppBrowserActivity
@@ -455,4 +456,49 @@ class GeckoBrowserApiImpl : GeckoBrowserApi {
         currentActivity.startActivity(intent)
     }
 
+    override fun shutdown() {
+        logger.debug("$TAG: Shutting down GeckoView engine")
+
+        // 1. Remove the browser fragment so its onDestroyView runs while the
+        //    runtime is still alive. This tears down EngineView, features, and
+        //    clears component references cleanly.
+        try {
+            val fragmentActivity = activity as? FragmentActivity
+            if (fragmentActivity != null && !fragmentActivity.isFinishing && !fragmentActivity.isDestroyed) {
+                val fm = fragmentActivity.supportFragmentManager
+                if (!fm.isStateSaved) {
+                    val existing = fm.findFragmentById(FRAGMENT_CONTAINER_ID)
+                    if (existing != null) {
+                        fm.beginTransaction().remove(existing).commitNow()
+                        logger.debug("$TAG: Browser fragment removed")
+                    }
+                }
+            }
+        } catch (e: Exception) {
+            logger.error("$TAG: Error removing browser fragment", e)
+        }
+
+        // 2. Stop component-level services
+        try {
+            GlobalComponents.components?.let { components ->
+                // Stop the FxA web channel feature
+                runCatching { components.services.fxaWebChannelFeature.stop() }
+
+                // Close the account manager
+                runCatching { components.backgroundServices.accountManager.close() }
+            }
+        } catch (e: Exception) {
+            logger.error("$TAG: Error during component shutdown", e)
+        }
+
+        // 3. Shutdown GeckoRuntime (safe now that no views reference it)
+        try {
+            EngineProvider.shutdown()
+        } catch (e: Exception) {
+            logger.error("$TAG: Error shutting down GeckoRuntime", e)
+        }
+
+        isGeckoInitialized = false
+    }
+
 }

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/pigeons/Gecko.g.kt

@@ -4847,6 +4847,7 @@ interface GeckoBrowserApi {
   fun openInCustomTab(url: String, private: Boolean, contextId: String?)
   fun isDefaultBrowser(): Boolean
   fun requestDefaultBrowser()
+  fun shutdown()
 
   companion object {
     /** The codec used by GeckoBrowserApi. */
@@ -4980,6 +4981,22 @@ interface GeckoBrowserApi {
           channel.setMessageHandler(null)
         }
       }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.flutter_mozilla_components.GeckoBrowserApi.shutdown$separatedMessageChannelSuffix", codec)
+        if (api != null) {
+          channel.setMessageHandler { _, reply ->
+            val wrapped: List<Any?> = try {
+              api.shutdown()
+              listOf(null)
+            } catch (exception: Throwable) {
+              GeckoPigeonUtils.wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
     }
   }
 }

packages/flutter_mozilla_components/lib/src/domain/services/gecko_browser.dart

@@ -64,4 +64,8 @@ class GeckoBrowserService {
   Future<void> requestDefaultBrowser() {
     return _api.requestDefaultBrowser();
   }
+
+  Future<void> shutdown() {
+    return _api.shutdown();
+  }
 }

packages/flutter_mozilla_components/lib/src/pigeons/gecko.g.dart

@@ -5805,6 +5805,28 @@ class GeckoBrowserApi {
       return;
     }
   }
+
+  Future<void> shutdown() async {
+    final pigeonVar_channelName = 'dev.flutter.pigeon.flutter_mozilla_components.GeckoBrowserApi.shutdown$pigeonVar_messageChannelSuffix';
+    final pigeonVar_channel = BasicMessageChannel<Object?>(
+      pigeonVar_channelName,
+      pigeonChannelCodec,
+      binaryMessenger: pigeonVar_binaryMessenger,
+    );
+    final Future<Object?> pigeonVar_sendFuture = pigeonVar_channel.send(null);
+    final pigeonVar_replyList = await pigeonVar_sendFuture as List<Object?>?;
+    if (pigeonVar_replyList == null) {
+      throw _createConnectionError(pigeonVar_channelName);
+    } else if (pigeonVar_replyList.length > 1) {
+      throw PlatformException(
+        code: pigeonVar_replyList[0]! as String,
+        message: pigeonVar_replyList[1] as String?,
+        details: pigeonVar_replyList[2],
+      );
+    } else {
+      return;
+    }
+  }
 }
 
 class GeckoSyncApi {

packages/flutter_mozilla_components/pigeons/gecko.dart

@@ -1151,6 +1151,7 @@ abstract class GeckoBrowserApi {
   });
   bool isDefaultBrowser();
   void requestDefaultBrowser();
+  void shutdown();
 }
 
 enum SyncEngineValue { history, bookmarks, tabs }