Add warning while enabling email verification

lib/l10n/arb/app_en.arb

@@ -92,6 +92,7 @@
   "importCodeDelimiterInfo": "The codes can be separated by a comma or a new line",
   "selectFile": "Select file",
   "emailVerificationToggle": "Email verification",
+  "emailVerificationEnableWarning": "If you are storing the 2FA to your email with us, turning on email verification could result in a deadlock. If you are locked out of one service, you might not be able to log in to the other.",
   "authToChangeEmailVerificationSetting": "Please authenticate to change email verification",
   "authToViewYourRecoveryKey": "Please authenticate to view your recovery key",
   "authToChangeYourEmail": "Please authenticate to change your email",

lib/ui/settings/security_section_widget.dart

@@ -179,7 +179,7 @@ class _SecuritySectionWidgetState extends State<SecuritySectionWidget> {
     );
   }
 
-  Future<void> updateEmailMFA(bool isEnabled) async {
+  Future<void> updateEmailMFA(bool enableEmailMFA) async {
     try {
       final UserDetails details =
           await UserService.instance.getUserDetailsV2(memoryCount: false);
@@ -195,7 +195,21 @@ class _SecuritySectionWidgetState extends State<SecuritySectionWidget> {
           ),
         );
       }
-      await UserService.instance.updateEmailMFA(isEnabled);
+      if (enableEmailMFA) {
+        await showChoiceActionSheet(
+          context,
+          title: context.l10n.warning,
+          body: context.l10n.emailVerificationEnableWarning,
+          isCritical: true,
+          firstButtonOnTap: () async {
+            await UserService.instance.updateEmailMFA(enableEmailMFA);
+          },
+          secondButtonLabel: context.l10n.cancel,
+          firstButtonLabel: context.l10n.iUnderStand,
+        );
+      } else {
+        await UserService.instance.updateEmailMFA(enableEmailMFA);
+      }
     } catch (e) {
       showToast(context, context.l10n.somethingWentWrongMessage);
     }