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.
quitAction = new QAction(platformStyle->TextColorIcon(":/icons/quit"), tr("E&xit"), this);
    quitAction->setStatusTip(tr("Quit application"));
    quitAction->setShortcut(QKeySequence(Qt::CTRL + Qt::Key_Q));
    quitAction->setMenuRole(QAction::QuitRole);
    aboutAction = new QAction(platformStyle->TextColorIcon(":/icons/about"), tr("&About %1").arg(tr(PACKAGE_NAME)), this);
    aboutAction->setStatusTip(tr("Show information about %1").arg(tr(PACKAGE_NAME)));
    aboutAction->setMenuRole(QAction::AboutRole);
    aboutAction->setEnabled(false);
    aboutQtAction = new QAction(platformStyle->TextColorIcon(":/icons/about_qt"), tr("About &Qt"), this);
    aboutQtAction->setStatusTip(tr("Show information about Qt"));
    aboutQtAction->setMenuRole(QAction::AboutQtRole);
    optionsAction = new QAction(platformStyle->TextColorIcon(":/icons/options"), tr("&Options..."), this);
    optionsAction->setStatusTip(tr("Modify configuration options for %1").arg(tr(PACKAGE_NAME)));
    optionsAction->setMenuRole(QAction::PreferencesRole);
    optionsAction->setEnabled(false);
    toggleHideAction = new QAction(platformStyle->TextColorIcon(":/icons/about"), tr("&Show / Hide"), this);
    toggleHideAction->setStatusTip(tr("Show or hide the main Window"));
    encryptWalletAction = new QAction(platformStyle->TextColorIcon(":/icons/lock_closed"), tr("&Encrypt Wallet..."), this);
    encryptWalletAction->setStatusTip(tr("Encrypt the private keys that belong to your wallet"));
    encryptWalletAction->setCheckable(true);
    backupWalletAction = new QAction(platformStyle->TextColorIcon(":/icons/filesave"), tr("&Backup Wallet..."), this);
    backupWalletAction->setStatusTip(tr("Backup wallet to another location"));
    changePassphraseAction = new QAction(platformStyle->TextColorIcon(":/icons/key"), tr("&Change Passphrase..."), this);
    changePassphraseAction->setStatusTip(tr("Change the passphrase used for wallet encryption"));
    signMessageAction = new QAction(platformStyle->TextColorIcon(":/icons/edit"), tr("Sign &message..."), this);
    signMessageAction->setStatusTip(tr("Sign messages with your Bitcoin addresses to prove you own them"));
    verifyMessageAction = new QAction(platformStyle->TextColorIcon(":/icons/verify"), tr("&Verify message..."), this);
    verifyMessageAction->setStatusTip(tr("Verify messages to ensure they were signed with specified Bitcoin addresses"));
    openRPCConsoleAction = new QAction(platformStyle->TextColorIcon(":/icons/debugwindow"), tr("&Debug window"), this);
    openRPCConsoleAction->setStatusTip(tr("Open debugging and diagnostic console"));