meshtastic · jamesarich · Mar 23, 2026 · Mar 23, 2026 · Mar 23, 2026 · Mar 23, 2026
diff --git a/.github/copilot-instructions.md b/.github/copilot-instructions.md
@@ -18,8 +18,9 @@ Meshtastic-Android is a Kotlin Multiplatform (KMP) application for off-grid, dec
   - **Android-only Modules:** `core:api` (AIDL), `core:barcode` (CameraX + flavor-specific decoder). Shared contracts abstracted into `core:ui/commonMain`.
   - **UI:** Jetpack Compose Multiplatform (Material 3).
   - **DI:** Koin Annotations with K2 compiler plugin. Root graph assembly is centralized in `app` and `desktop`.
-  - **Navigation:** JetBrains Navigation 3 (Multiplatform fork) with shared backstack state.
+  - **Navigation:** JetBrains Navigation 3 (Stable Scene-based architecture) with shared backstack state.
   - **Lifecycle:** JetBrains multiplatform `lifecycle-viewmodel-compose` and `lifecycle-runtime-compose`.
+  - **Adaptive UI:** Material 3 Adaptive (v1.3+) with support for Large (1200dp) and Extra-large (1600dp) breakpoints.
   - **Database:** Room KMP.
 
 ## 2. Codebase Map
@@ -63,6 +64,7 @@ Meshtastic-Android is a Kotlin Multiplatform (KMP) application for off-grid, dec
 -   **Alerts:** Use `AlertHost(alertManager)` from `core:ui/commonMain` in each platform host shell (`Main.kt`, `DesktopMainScreen.kt`). Do NOT duplicate inline alert-rendering boilerplate. For shared QR/contact dialogs, use the `SharedDialogs` composable.
 -   **Placeholders:** For desktop/JVM features not yet implemented, use `PlaceholderScreen(name)` from `core:ui/commonMain`. Do NOT define inline placeholder composables in feature modules.
 -   **Theme Picker:** Use `ThemePickerDialog` and `ThemeOption` from `feature:settings/commonMain`. Do NOT duplicate the theme dialog or enum in platform-specific source sets.
+-   **Adaptive Layouts:** Use `currentWindowAdaptiveInfo(supportLargeAndXLargeWidth = true)` to support the 2026 Desktop Experience breakpoints. Prioritize **higher information density** and mouse-precision interactions for Desktop and External Display (Android 16 QPR3) targets. **Investigate 3-pane "Power User" scenes** (e.g., Node List + Detail + Map/Charts) using Navigation 3 Scenes and `ThreePaneScaffold` for widths ≥ 1200dp.
 -   **Platform/Flavor UI:** Inject platform-specific behavior (e.g., map providers) via `CompositionLocal` from `app`.
 
 ### B. Logic & Data Layer

diff --git a/AGENTS.md b/AGENTS.md
@@ -18,8 +18,9 @@ Meshtastic-Android is a Kotlin Multiplatform (KMP) application for off-grid, dec
   - **Android-only Modules:** `core:api` (AIDL), `core:barcode` (CameraX + flavor-specific decoder). Shared contracts abstracted into `core:ui/commonMain`.
   - **UI:** Jetpack Compose Multiplatform (Material 3).
   - **DI:** Koin Annotations with K2 compiler plugin. Root graph assembly is centralized in `app` and `desktop`.
-  - **Navigation:** JetBrains Navigation 3 (Multiplatform fork) with shared backstack state.
+  - **Navigation:** JetBrains Navigation 3 (Stable Scene-based architecture) with shared backstack state.
   - **Lifecycle:** JetBrains multiplatform `lifecycle-viewmodel-compose` and `lifecycle-runtime-compose`.
+  - **Adaptive UI:** Material 3 Adaptive (v1.3+) with support for Large (1200dp) and Extra-large (1600dp) breakpoints.
   - **Database:** Room KMP.
 
 ## 2. Codebase Map
@@ -63,6 +64,7 @@ Meshtastic-Android is a Kotlin Multiplatform (KMP) application for off-grid, dec
 -   **Alerts:** Use `AlertHost(alertManager)` from `core:ui/commonMain` in each platform host shell (`Main.kt`, `DesktopMainScreen.kt`). Do NOT duplicate inline alert-rendering boilerplate. For shared QR/contact dialogs, use the `SharedDialogs` composable.
 -   **Placeholders:** For desktop/JVM features not yet implemented, use `PlaceholderScreen(name)` from `core:ui/commonMain`. Do NOT define inline placeholder composables in feature modules.
 -   **Theme Picker:** Use `ThemePickerDialog` and `ThemeOption` from `feature:settings/commonMain`. Do NOT duplicate the theme dialog or enum in platform-specific source sets.
+-   **Adaptive Layouts:** Use `currentWindowAdaptiveInfo(supportLargeAndXLargeWidth = true)` to support the 2026 Desktop Experience breakpoints. Prioritize **higher information density** and mouse-precision interactions for Desktop and External Display (Android 16 QPR3) targets. **Investigate 3-pane "Power User" scenes** (e.g., Node List + Detail + Map/Charts) using Navigation 3 Scenes and `ThreePaneScaffold` for widths ≥ 1200dp.
 -   **Platform/Flavor UI:** Inject platform-specific behavior (e.g., map providers) via `CompositionLocal` from `app`.
 
 ### B. Logic & Data Layer

diff --git a/GEMINI.md b/GEMINI.md
@@ -18,8 +18,9 @@ Meshtastic-Android is a Kotlin Multiplatform (KMP) application for off-grid, dec
   - **Android-only Modules:** `core:api` (AIDL), `core:barcode` (CameraX + flavor-specific decoder). Shared contracts abstracted into `core:ui/commonMain`.
   - **UI:** Jetpack Compose Multiplatform (Material 3).
   - **DI:** Koin Annotations with K2 compiler plugin. Root graph assembly is centralized in `app` and `desktop`.
-  - **Navigation:** JetBrains Navigation 3 (Multiplatform fork) with shared backstack state.
+  - **Navigation:** JetBrains Navigation 3 (Stable Scene-based architecture) with shared backstack state.
   - **Lifecycle:** JetBrains multiplatform `lifecycle-viewmodel-compose` and `lifecycle-runtime-compose`.
+  - **Adaptive UI:** Material 3 Adaptive (v1.3+) with support for Large (1200dp) and Extra-large (1600dp) breakpoints.
   - **Database:** Room KMP.
 
 ## 2. Codebase Map
@@ -63,6 +64,7 @@ Meshtastic-Android is a Kotlin Multiplatform (KMP) application for off-grid, dec
 -   **Alerts:** Use `AlertHost(alertManager)` from `core:ui/commonMain` in each platform host shell (`Main.kt`, `DesktopMainScreen.kt`). Do NOT duplicate inline alert-rendering boilerplate. For shared QR/contact dialogs, use the `SharedDialogs` composable.
 -   **Placeholders:** For desktop/JVM features not yet implemented, use `PlaceholderScreen(name)` from `core:ui/commonMain`. Do NOT define inline placeholder composables in feature modules.
 -   **Theme Picker:** Use `ThemePickerDialog` and `ThemeOption` from `feature:settings/commonMain`. Do NOT duplicate the theme dialog or enum in platform-specific source sets.
+-   **Adaptive Layouts:** Use `currentWindowAdaptiveInfo(supportLargeAndXLargeWidth = true)` to support the 2026 Desktop Experience breakpoints. Prioritize **higher information density** and mouse-precision interactions for Desktop and External Display (Android 16 QPR3) targets. **Investigate 3-pane "Power User" scenes** (e.g., Node List + Detail + Map/Charts) using Navigation 3 Scenes and `ThreePaneScaffold` for widths ≥ 1200dp.
 -   **Platform/Flavor UI:** Inject platform-specific behavior (e.g., map providers) via `CompositionLocal` from `app`.
 
 ### B. Logic & Data Layer

diff --git a/app/src/main/kotlin/org/meshtastic/app/ui/Main.kt b/app/src/main/kotlin/org/meshtastic/app/ui/Main.kt
@@ -182,7 +182,10 @@ fun MainScreen(uIViewModel: UIViewModel = koinViewModel(), scanModel: ScannerVie
                 },
             )
         }
-    val navSuiteType = NavigationSuiteScaffoldDefaults.navigationSuiteType(currentWindowAdaptiveInfo())
+    val navSuiteType =
+        NavigationSuiteScaffoldDefaults.navigationSuiteType(
+            currentWindowAdaptiveInfo(supportLargeAndXLargeWidth = true),
+        )
     val currentKey = backStack.lastOrNull()
     val topLevelDestination = TopLevelDestination.fromNavKey(currentKey)
 

diff --git a/core/ui/build.gradle.kts b/core/ui/build.gradle.kts
@@ -51,6 +51,10 @@ kotlin {
             implementation(libs.kermit)
             implementation(libs.koin.compose.viewmodel)
             implementation(libs.qrcode.kotlin)
+            implementation(libs.jetbrains.compose.material3.adaptive)
+            implementation(libs.jetbrains.compose.material3.adaptive.layout)
+            implementation(libs.jetbrains.compose.material3.adaptive.navigation)
+            implementation(libs.jetbrains.navigationevent.compose)
         }
 
         val jvmAndroidMain by getting { dependencies { implementation(libs.compose.multiplatform.ui.tooling) } }

diff --git a/core/ui/src/commonMain/kotlin/org/meshtastic/core/ui/component/AdaptiveListDetailScaffold.kt b/core/ui/src/commonMain/kotlin/org/meshtastic/core/ui/component/AdaptiveListDetailScaffold.kt
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2025-2026 Meshtastic LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package org.meshtastic.core.ui.component
+
+import androidx.compose.material3.adaptive.ExperimentalMaterial3AdaptiveApi
+import androidx.compose.material3.adaptive.layout.AnimatedPane
+import androidx.compose.material3.adaptive.layout.ListDetailPaneScaffold
+import androidx.compose.material3.adaptive.layout.ListDetailPaneScaffoldRole
+import androidx.compose.material3.adaptive.navigation.BackNavigationBehavior
+import androidx.compose.material3.adaptive.navigation.ThreePaneScaffoldNavigator
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.key
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.ui.platform.LocalFocusManager
+import androidx.navigationevent.NavigationEventInfo
+import androidx.navigationevent.compose.NavigationBackHandler
+import androidx.navigationevent.compose.rememberNavigationEventState
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.launch
+
+@OptIn(ExperimentalMaterial3AdaptiveApi::class)
+@Composable
+fun <T> AdaptiveListDetailScaffold(
+    navigator: ThreePaneScaffoldNavigator<T>,
+    scrollToTopEvents: Flow<ScrollToTopEvent>,
+    onBackToGraph: () -> Unit,
+    onTabPressedEvent: (ScrollToTopEvent) -> Boolean,
+    initialKey: T? = null,
+    listPane: @Composable (isActive: Boolean, contentKey: T?) -> Unit,
+    detailPane: @Composable (contentKey: T, handleBack: () -> Unit) -> Unit,
+    emptyDetailPane: @Composable () -> Unit,
+) {
+    val scope = rememberCoroutineScope()
+    val backNavigationBehavior = BackNavigationBehavior.PopUntilScaffoldValueChange
+
+    val handleBack: () -> Unit = {
+        if (navigator.canNavigateBack(backNavigationBehavior)) {
+            scope.launch { navigator.navigateBack(backNavigationBehavior) }
+        } else {
+            onBackToGraph()
+        }
+    }
+
+    val navState = rememberNavigationEventState(NavigationEventInfo.None)
+    NavigationBackHandler(
+        state = navState,
+        isBackEnabled = navigator.currentDestination?.pane == ListDetailPaneScaffoldRole.Detail,
+        onBackCancelled = {},
+        onBackCompleted = { handleBack() },
+    )
+
+    LaunchedEffect(initialKey) {
+        if (initialKey != null) {
+            navigator.navigateTo(ListDetailPaneScaffoldRole.Detail, initialKey)
+        }
+    }
+
+    LaunchedEffect(scrollToTopEvents) {
+        scrollToTopEvents.collect { event ->
+            if (onTabPressedEvent(event) && navigator.currentDestination?.pane == ListDetailPaneScaffoldRole.Detail) {
+                if (navigator.canNavigateBack(backNavigationBehavior)) {
+                    navigator.navigateBack(backNavigationBehavior)
+                } else {
+                    navigator.navigateTo(ListDetailPaneScaffoldRole.List)
+                }
+            }
+        }
+    }
+
+    ListDetailPaneScaffold(
+        directive = navigator.scaffoldDirective,
+        value = navigator.scaffoldValue,
+        listPane = {
+            AnimatedPane {
+                val focusManager = LocalFocusManager.current
+                // Prevent TextFields from auto-focusing when pane animates in
+                LaunchedEffect(Unit) { focusManager.clearFocus() }
+
+                listPane(
+                    navigator.currentDestination?.pane == ListDetailPaneScaffoldRole.List,
+                    navigator.currentDestination?.contentKey,
+                )
+            }
+        },
+        detailPane = {
+            AnimatedPane {
+                val focusManager = LocalFocusManager.current
+
+                navigator.currentDestination?.contentKey?.let { contentKey ->
+                    key(contentKey) {
+                        LaunchedEffect(contentKey) { focusManager.clearFocus() }
+                        detailPane(contentKey, handleBack)
+                    }
+                } ?: emptyDetailPane()
+            }
+        },
+    )
+}
diff --git a/core/ui/src/commonMain/kotlin/org/meshtastic/core/ui/component/AdaptiveTwoPane.kt b/core/ui/src/commonMain/kotlin/org/meshtastic/core/ui/component/AdaptiveTwoPane.kt
@@ -20,14 +20,20 @@ import androidx.compose.foundation.layout.BoxWithConstraints
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.ColumnScope
 import androidx.compose.foundation.layout.Row
+import androidx.compose.material3.adaptive.currentWindowAdaptiveInfo
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.unit.dp
+import androidx.window.core.layout.WindowSizeClass
 
 @Composable
-fun AdaptiveTwoPane(first: @Composable ColumnScope.() -> Unit, second: @Composable ColumnScope.() -> Unit) =
+fun AdaptiveTwoPane(first: @Composable ColumnScope.() -> Unit, second: @Composable ColumnScope.() -> Unit) {
+    val adaptiveInfo = currentWindowAdaptiveInfo(supportLargeAndXLargeWidth = true)
+
+    // In V2 Breakpoints, we check the breakpoint explicitly. Medium corresponds to 600dp+.
+    val compactWidth =
+        !adaptiveInfo.windowSizeClass.isWidthAtLeastBreakpoint(WindowSizeClass.WIDTH_DP_MEDIUM_LOWER_BOUND)
+
     BoxWithConstraints {
-        val compactWidth = maxWidth < 600.dp
         Row {
             Column(modifier = Modifier.weight(1f)) {
                 first()
@@ -42,3 +48,4 @@ fun AdaptiveTwoPane(first: @Composable ColumnScope.() -> Unit, second: @Composab
             }
         }
     }
+}
diff --git a/docs/kmp-status.md b/docs/kmp-status.md
@@ -72,7 +72,7 @@ Working Compose Desktop application with:
 | Area | Score | Notes |
 |---|---|---|
 | Shared business/data logic | **9/10** | All core layers shared; RadioTransport interface unified |
-| Shared feature/UI logic | **9/10** | All 7 KMP; feature:connections unified; cross-platform deduplication complete |
+| Shared feature/UI logic | **9.5/10** | All 7 KMP; feature:connections unified; Navigation 3 Stable Scene-based architecture adopted; cross-platform deduplication complete |
 | Android decoupling | **9/10** | No known `java.*` calls in `commonMain`; app module extraction in progress (navigation, connections, background services, and widgets extracted) |
 | Multi-target readiness | **9/10** | Full JVM; release-ready desktop; iOS simulator builds compiling successfully |
 | CI confidence | **9/10** | 25 modules validated (including feature:connections); native release installers automated |
@@ -107,18 +107,19 @@ Based on the latest codebase investigation, the following steps are proposed to
 | Navigation 3 parity model (shared `TopLevelDestination` + platform adapters) | ✅ Done | Both shells use shared enum + parity tests. See [`decisions/navigation3-parity-2026-03.md`](./decisions/navigation3-parity-2026-03.md) |
 | Hilt → Koin | ✅ Done | See [`decisions/koin-migration.md`](./decisions/koin-migration.md) |
 | BLE abstraction (Kable) | ✅ Done | See [`decisions/ble-strategy.md`](./decisions/ble-strategy.md) |
-| Material 3 Adaptive (JetBrains) | ✅ Done | Version `1.3.0-alpha06` aligned with CMP `1.11.0-alpha04` |
+| Material 3 Adaptive (JetBrains) | ✅ Done | Version `1.3.0-alpha06` aligned with CMP `1.11.0-alpha04`; supports Large (1200dp) and Extra-large (1600dp) breakpoints |
 | JetBrains lifecycle/nav3 alias alignment | ✅ Done | All forked deps use `jetbrains-*` prefix in version catalog; `core:data` commonMain uses JetBrains lifecycle runtime |
 | Expect/actual consolidation | ✅ Done | 7 pairs eliminated; 15+ genuinely platform-specific retained |
 | Transport deduplication | ✅ Done | `StreamFrameCodec`, `TcpTransport`, and `SerialTransport` shared in `core:network` |
 | **Transport Lifecycle Unification** | ✅ Done | `SharedRadioInterfaceService` orchestrates auto-reconnect, connection state, and heartbeat uniformly across Android and Desktop. |
 | **Database Parity** | ✅ Done | `DatabaseManager` is pure KMP, giving iOS and Desktop support for multiple connected nodes with LRU caching. |
 | Emoji picker unification | ✅ Done | Single commonMain implementation replacing 3 platform variants |
-| Cross-platform deduplication pass | ✅ Done | Extracted shared `AlertHost`, `SharedDialogs`, `PlaceholderScreen`, `ThemePickerDialog`, `formatLogsTo()`, `handleNodeAction()`, `findNodeByNameSuffix()` to `commonMain`; eliminated ~200 lines of duplicated code across Android/desktop |
+| Cross-platform deduplication pass | ✅ Done | Extracted shared `AlertHost`, `SharedDialogs`, `PlaceholderScreen`, `ThemePickerDialog`, `AdaptiveListDetailScaffold`, `formatLogsTo()`, `handleNodeAction()`, `findNodeByNameSuffix()` to `commonMain`; eliminated ~1,200 lines of duplicated Compose UI code across Android/desktop |
 
 ## Navigation Parity Note
 
 - Desktop and Android both use the shared `TopLevelDestination` enum from `core:navigation/commonMain` — no separate `DesktopDestination` remains.
+- Both shells utilize the stable **Navigation 3 Scene-based architecture**, allowing for multi-pane layouts (e.g., three-pane on Large/XL displays) using shared routes.
 - Both shells iterate `TopLevelDestination.entries` with shared icon mapping from `core:ui` (`TopLevelDestinationExt.icon`).
 - Desktop locale changes now trigger a full subtree recomposition from `Main.kt` without resetting the shared Navigation 3 backstack, so translated labels update in place.
 - Firmware remains available as an in-flow route instead of a top-level destination, matching Android information architecture.