How to set the icon size for a specific QTabBar button?

Cesar

I'm trying to create an effect similar to this gif:

While you are hovering over the tab button it shows a text and also resizes the icon.

I was reading the docs about the property icon-size it says it supports QTabBar, but adding the property into the tab stylesheet, has no effect when the button is being hovered.

I'm doing something wrong or it's a 'bug'?

QTabBar::tab:hover {
     font-size: 12pt;
     icon-size: 64px 64px;
     color: rgb(255, 255, 255);
     background: transparent;
}

As I couldn't get it working with a stylesheet, I tried using an event filter:

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    ui->tabWidget->tabBar()->installEventFilter(this);
}

bool MainWindow::eventFilter(QObject *obj, QEvent *event)
{

        if (event->type() == QEvent::HoverEnter)
        {
            QTabBar *tabbar = static_cast<QTabBar*>(obj);
            tabbar->setIconSize(QSize(40, 40));
        }
        else if (event->type() == QEvent::HoverLeave)
        {
            QTabBar *tabbar = static_cast<QTabBar*>(obj);
            tabbar->setIconSize(QSize(32,32));
        }
    
       // pass the event on to the parent class
       return QMainWindow::eventFilter(obj, event);
}

Result:

Whenever any tab button has hovered, it resizes all icons.

How I could resize just the tab button under the mouse instead of the entire "QTabBar"?

Tab stylesheet options from the gif above:


QTabWidget::pane {
	background: transparent;
}

QTabBar::tab {
    font-size: 12pt;
    color: rgba(255, 255, 255, 0);
	background: transparent;
}

QTabBar::tab:hover {
     font-size: 12pt;
     color: rgb(255, 255, 255);
     background: transparent;
}

QTabBar::tab:selected {
    background: transparent;
}

I don't understand what's going on with the text, the tab text is "Tab" but it's cropping the "T".

Why the tab pane background is not getting transparent?