diff --git a/test/probe/ui_scale_probe_test.dart b/test/probe/ui_scale_probe_test.dart
new file mode 100644
index 00000000..8a83d318
--- /dev/null
+++ b/test/probe/ui_scale_probe_test.dart
@@ -0,0 +1,89 @@
+import 'dart:async';
+
+import 'package:flutter/services.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:querya_desktop/app/app.dart';
+import 'package:querya_desktop/core/layout/ui_scale_controller.dart';
+import 'package:querya_desktop/features/main_screen/main_screen.dart';
+import 'package:querya_desktop/features/postgresql/postgresql_connection_form.dart';
+import 'package:querya_desktop/features/settings/preferences_dialog.dart';
+
+import '../e2e/helpers/e2e_app_harness.dart';
+import '../e2e/helpers/e2e_command_palette_helper.dart';
+import '../support/layout_overflow.dart';
+
+/// PROBE, not a regression test: counts layout overflows of a few screens at
+/// several interface scales and window sizes, and fails at the end with the
+/// table so the numbers are in the CI log.
+void main() {
+  final app = E2eAppHarness();
+  setUpAll(app.setUpAll);
+  tearDownAll(app.tearDownAll);
+
+  final rows = <String>[];
+
+  String firstLine(FlutterErrorDetails d) {
+    final s = d.exceptionAsString().split('\n').first;
+    return s.length > 110 ? s.substring(0, 110) : s;
+  }
+
+  Future<void> measure(
+    WidgetTester tester,
+    String label,
+    Future<void> Function() action,
+  ) async {
+    final errors = await collectOverflowErrorsDuring(() async {
+      await action();
+      await pumpFrames(tester, count: 10);
+    });
+    final distinct = <String>{for (final e in errors) firstLine(e)};
+    rows.add('$label: ${errors.length} overflows'
+        '${distinct.isEmpty ? '' : '  e.g. ${distinct.take(2).join(' | ')}'}');
+    // The probe reads the errors; they must not fail the test run.
+    tester.takeException();
+  }
+
+  for (final size in const [Size(1280, 720), Size(900, 600)]) {
+    for (final scale in const [0.75, 1.0, 1.25, 1.5, 2.0]) {
+      testWidgets('scale $scale at ${size.width.toInt()}x${size.height.toInt()}',
+          (tester) async {
+        await tester.runAsync(() => UiScaleController.instance.commitScale(scale));
+        await tester.binding.setSurfaceSize(size);
+        addTearDown(() => tester.binding.setSurfaceSize(null));
+        final tag = 'scale=$scale ${size.width.toInt()}x${size.height.toInt()}';
+
+        await measure(tester, '$tag shell', () async {
+          await tester.pumpWidget(const QueryaApp());
+          await pumpFrames(tester, count: 20);
+        });
+        final ctx = tester.element(find.byType(MainScreen));
+
+        await measure(tester, '$tag preferences', () async {
+          showPreferencesDialog(ctx);
+          await pumpFrames(tester, count: 20);
+        });
+        await tester.sendKeyEvent(LogicalKeyboardKey.escape);
+        await pumpFrames(tester, count: 10);
+
+        await measure(tester, '$tag postgres form', () async {
+          unawaited(showPostgresConnectionForm(ctx));
+          await pumpFrames(tester, count: 20);
+        });
+        await tester.sendKeyEvent(LogicalKeyboardKey.escape);
+        await pumpFrames(tester, count: 10);
+
+        await measure(tester, '$tag command palette', () async {
+          await E2ePalette.open(tester);
+        });
+        await tester.sendKeyEvent(LogicalKeyboardKey.escape);
+        await tester.sendKeyEvent(LogicalKeyboardKey.escape);
+        await app.close(tester);
+      });
+    }
+  }
+
+  test('report', () {
+    fail('UI SCALE PROBE\n${rows.join('\n')}');
+  });
+}