Using master. During startup, if you open `Window` -> `Console` and try and execute any command (can be garbage) `bitcoin-qt` will crash:
```bash
On branch pull/16118/local-merge

Process 89287 launched: '/Users/michael/github/bitcoin/src/qt/bitcoin-qt' (x86_64)
2019-05-29 09:57:56.276746-0400 bitcoin-qt[89287:939924] MessageTracer: Falling back to default whitelist
Process 89287 stopped
* thread #1, name = 'bitcoin-main', queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
    frame #0: 0x00000001015158ba QtWidgets`QCompleter::popup() const + 10
QtWidgets`QCompleter::popup:
->  0x1015158ba <+10>: movq   0x8(%rdi), %rbx
    0x1015158be <+14>: movq   0x88(%rbx), %rax
    0x1015158c5 <+21>: testq  %rax, %rax
    0x1015158c8 <+24>: jne    0x101515942               ; <+146>
Target 0: (bitcoin-qt) stopped.
```

Not sure if just disabling the menu, like in #16118 would be ok, as a user might actually want to be able to run a command.
platformStyle->SingleColorImage(ICON_MAPPING[i].source).scaled(QSize(consoleFontSize*2, consoleFontSize*2), Qt::IgnoreAspectRatio, Qt::SmoothTransformation));
    }
    // 
    QFontInfo fixedFontInfo(GUIUtil::fixedPitchFont());
    ui->messagesWidget->document()->setDefaultStyleSheet(
        QString(
                "table { }"
                "td.time { color: #808080; font-size: %2; padding-top: 3px; } "
                "td.message { font-family: %1; font-size: %2; white-space:pre-wrap; } "
                "td.cmd-request { color: #006060; } "
                "td.cmd-error { color: red; } "
                ".secwarning { color: red; }"
                "b { color: #006060; } "
            ).arg(fixedFontInfo.family(), QString("%1pt").arg(consoleFontSize))
        );
#ifdef Q_OS_MAC
    QString clsKey = "(⌘)-L";
#else
    QString clsKey = "Ctrl-L";
#endif
    message(CMD_REPLY, (tr("Welcome to the %1 RPC console.").arg(tr(PACKAGE_NAME)) + "<br>" +
                        tr("Use up and down arrows to navigate history, and %1 to clear screen.").arg("<b>"+clsKey+"</b>") + "<br>" +
                        tr("Type %1 for an overview of available commands.").arg("<b>help</b>") + "<br>" +
                        tr("For more information on using this console type %1.").arg("<b>help-console</b>") +
                        "<br><span class=\"secwarning\"><br>" +
                        tr("WARNING: Scammers have been active, telling users to type commands here, stealing their wallet contents. Do not use this console without fully understanding the ramifications of a command.") +
                        "</span>"),
                        true);
}
void RPCConsole::keyPressEvent(QKeyEvent *event)