Using master (98958c81f5065a5de13699d46995d278ecb6709e) with Qt `5.12.3` (also tested with depends) with multiple wallets available. None are shown in the `Open Wallet ->` menu in the gui. The wallets can be loaded from the console, bitcoin-cli etc.
#ifndef BITCOIN_QT_BITCOINGUI_H
#define BITCOIN_QT_BITCOINGUI_H
#if defined(HAVE_CONFIG_H)
#include <config/bitcoin-config.h>
#endif
#include <qt/optionsdialog.h>
#include <amount.h>
#include <QLabel>
#include <QMainWindow>
#include <QMap>
#include <QPoint>
#include <QSystemTrayIcon>
#ifdef Q_OS_MAC
#include <qt/macos_appnap.h>
#endif
#include <memory>
class ClientModel;
class NetworkStyle;
class Notificator;