Merge branch 'learn-fb' into integration

packages/halkyon_app/test/password/widget/password_sheets_test.dart

@@ -3,6 +3,7 @@ import 'dart:convert';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:halkyon_app/halkyon_app.dart';
 import 'package:halkyon_app/testing.dart';
+import 'package:halkyon_ui/halkyon_ui.dart';
 import 'package:material_ui/material_ui.dart';
 
 /// A signed-in person's app as a test makes one: whose it is.
@@ -592,6 +593,20 @@ void main() {
 
       expect(find.text('Set up a password'), findsOneWidget);
       expect(find.text('Change password'), findsNothing);
+
+      // What it is, behind its question mark (decided 3 Nov 2026).
+      const what =
+          'Sign in with your email address, a password and an '
+          'authenticator app.';
+      expect(find.text(what), findsNothing);
+      await tester.tap(
+        find.descendant(
+          of: find.widgetWithText(ExplainedTitle, 'Set up a password'),
+          matching: find.byType(HelpButton),
+        ),
+      );
+      await tester.pumpAndSettle();
+      expect(find.text(what), findsOneWidget);
     });
 
     testWidgets('offers none to one without an address: a code mailed to '