diff --git a/pubspec.yaml b/pubspec.yaml
index 0a149fb4..af98c1fe 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -18,7 +18,7 @@ repository: https://github.com/postmeridiem/clide
 
 # Pre-push line-coverage floor. Ratchets up only — see D-66.
 # Reading: `awk -F: '/^coverage_floor:/ {gsub(/ /,"",$2); print $2}' pubspec.yaml`.
-coverage_floor: 89
+coverage_floor: 90
 
 # Project metadata (was project.yaml, folded in per D-056).
 # version: above is the single source of truth. The Makefile reads
diff --git a/test/builtin/welcome/dialog_test.dart b/test/builtin/welcome/dialog_test.dart
new file mode 100644
index 00000000..e32a3462
--- /dev/null
+++ b/test/builtin/welcome/dialog_test.dart
@@ -0,0 +1,128 @@
+/// Tests for the welcome view's open-project + not-a-repo dialogs.
+/// Uses a custom harness that wraps the standard widget harness in a
+/// DialogHost so kernel.dialog.show calls actually render their
+/// builder into the tree.
+library;
+
+import 'package:clide/builtin/welcome/src/welcome_view.dart';
+import 'package:clide/kernel/kernel.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+import '../../helpers/kernel_fixture.dart';
+import '../../helpers/widget_harness.dart';
+
+/// Wraps [harness] in a DialogHost rooted on the fixture's dialog
+/// router so kernel.dialog.show(...) calls render into the tree.
+Widget _harness(KernelFixture f, Widget child) {
+  return harness(
+    f,
+    DialogHost(router: f.services.dialog, child: child),
+  );
+}
+
+void main() {
+  group('WelcomeView dialogs', () {
+    late KernelFixture f;
+    setUp(() async {
+      f = await KernelFixture.create(
+        i18nCatalogs: {
+          'builtin.welcome': {
+            const Locale('en', 'US'): const {
+              'title': {'translation': 'clide'},
+              'subtitle': {'translation': 'IDE'},
+              'open-project': {'translation': 'Open project'},
+              'open-project.hint': {'translation': 'Pick a git repository'},
+              'tab.title': {'translation': 'Welcome'},
+            },
+          },
+        },
+      );
+    });
+    tearDown(() async => f.dispose());
+
+    testWidgets('MissingPluginException path renders the OpenProjectDialog', (tester) async {
+      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+        const MethodChannel('clide/window'),
+        (call) async {
+          if (call.method == 'pickDirectory') {
+            throw MissingPluginException();
+          }
+          return null;
+        },
+      );
+      tester.view.physicalSize = const Size(1200, 800);
+      tester.view.devicePixelRatio = 1.0;
+      addTearDown(tester.view.resetPhysicalSize);
+      addTearDown(tester.view.resetDevicePixelRatio);
+      await tester.pumpWidget(_harness(f, const WelcomeView()));
+      await tester.pumpAndSettle();
+      await tester.tap(find.text('Open folder…'));
+      await tester.pumpAndSettle();
+      expect(find.text('Open project'), findsOneWidget);
+      expect(find.text('Enter the path to a git repository.'), findsOneWidget);
+      expect(find.text('Cancel'), findsOneWidget);
+      expect(find.text('Open'), findsOneWidget);
+    });
+
+    testWidgets('OpenProjectDialog Cancel dismisses the modal', (tester) async {
+      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+        const MethodChannel('clide/window'),
+        (call) async => throw MissingPluginException(),
+      );
+      tester.view.physicalSize = const Size(1200, 800);
+      tester.view.devicePixelRatio = 1.0;
+      addTearDown(tester.view.resetPhysicalSize);
+      addTearDown(tester.view.resetDevicePixelRatio);
+      await tester.pumpWidget(_harness(f, const WelcomeView()));
+      await tester.pumpAndSettle();
+      await tester.tap(find.text('Open folder…'));
+      await tester.pumpAndSettle();
+      await tester.tap(find.text('Cancel'));
+      await tester.pumpAndSettle();
+      expect(find.text('Open project'), findsNothing);
+    });
+
+    testWidgets('OpenProjectDialog Open with empty path is a no-op', (tester) async {
+      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+        const MethodChannel('clide/window'),
+        (call) async => throw MissingPluginException(),
+      );
+      tester.view.physicalSize = const Size(1200, 800);
+      tester.view.devicePixelRatio = 1.0;
+      addTearDown(tester.view.resetPhysicalSize);
+      addTearDown(tester.view.resetDevicePixelRatio);
+      await tester.pumpWidget(_harness(f, const WelcomeView()));
+      await tester.pumpAndSettle();
+      await tester.tap(find.text('Open folder…'));
+      await tester.pumpAndSettle();
+      // Press Open with the text field empty.
+      await tester.tap(find.text('Open'));
+      await tester.pumpAndSettle();
+      // Dialog stays.
+      expect(find.text('Open project'), findsOneWidget);
+    });
+
+    testWidgets('OpenProjectDialog Open with a non-repo path keeps the dialog (project.open returns false)', (tester) async {
+      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+        const MethodChannel('clide/window'),
+        (call) async => throw MissingPluginException(),
+      );
+      tester.view.physicalSize = const Size(1200, 800);
+      tester.view.devicePixelRatio = 1.0;
+      addTearDown(tester.view.resetPhysicalSize);
+      addTearDown(tester.view.resetDevicePixelRatio);
+      await tester.pumpWidget(_harness(f, const WelcomeView()));
+      await tester.pumpAndSettle();
+      await tester.tap(find.text('Open folder…'));
+      await tester.pumpAndSettle();
+      await tester.enterText(find.byType(EditableText).last, '/tmp/clide-not-a-repo-${DateTime.now().microsecondsSinceEpoch}');
+      await tester.testTextInput.receiveAction(TextInputAction.done);
+      await tester.pumpAndSettle();
+      // project.open returns false → dialog stays open, "Opening…" no
+      // longer shows.
+      expect(find.text('Open project'), findsOneWidget);
+    });
+  });
+}