message: Fixes SingleInstance checkbox on macOS
diff: @@ -113,9 +113,6 @@ public:
  connect(privacy, &QLabel::linkActivated,
  [] { AboutDialog::openSharedInstance(AboutDialog::Privacy); });
  - mSingleInstance =
  - new QCheckBox(tr("Only allow a single running instance"), this);
  -
  QFormLayout *form = new QFormLayout;
  form->addRow(tr("User name:"), mName);
  form->addRow(tr("User email:"), mEmail);
  @@ -127,8 +124,13 @@ public:
  form->addRow(tr("Credentials:"), mStoreCredentials);
  form->addRow(QString(), privacy);
  + mSingleInstance =
  + new QCheckBox(tr("Only allow a single running instance"), this);
  +
  #if defined(Q_OS_LINUX) || defined(Q_OS_WIN)
  form->addRow(tr("Single instance:"), mSingleInstance);
  +#elif defined(Q_OS_MACX)
  + mSingleInstance->setVisible(false);
  #endif
  QVBoxLayout *layout = new QVBoxLayout(this);
  