It would be nice if the debug console had a little help page of itself, to describe the syntax to issue commands (also the nested ones), and a disclaimer that usage can be dangerous.

Maybe add a debug-console-only command like help that shows how to use nested commands and potentially other advanced tricks, and add 'for more information on using this console type XXX'.

See also:
- https://github.com/bitcoin/bitcoin/pull/7783#issuecomment-248274853
- https://github.com/bitcoin/bitcoin/issues/8544#issuecomment-240970925
- #8912 Console command paths cannot be specified correctly with backslashes
{
    setFontSize(consoleFontSize+1);
}
void RPCConsole::fontSmaller()
{
    setFontSize(consoleFontSize-1);
}
void RPCConsole::setFontSize(int newSize)
{
    QSettings settings;
    //
    if (newSize < FONT_RANGE.width() || newSize > FONT_RANGE.height())
        return;
    // 
    QString str = ui->messagesWidget->toHtml();
    // 
    str.replace(QString("font-size:%1pt").arg(consoleFontSize), QString("font-size:%1pt").arg(newSize));
    // 
    consoleFontSize = newSize;
    settings.setValue(fontSizeSettingsKey, consoleFontSize);
    // 
    float oldPosFactor = 1.0 / ui->messagesWidget->verticalScrollBar()->maximum() * ui->messagesWidget->verticalScrollBar()->value();
    clear(false);
    ui->messagesWidget->setHtml(str);
    ui->messagesWidget->verticalScrollBar()->setValue(oldPosFactor * ui->messagesWidget->verticalScrollBar()->maximum());
}
void RPCConsole::clear(bool clearHistory)