made the code actually compile

src/widgets/tooltipwidget.hpp

@@ -3,6 +3,7 @@
 
 #include <QLabel>
 #include <QWidget>
+#include <pajlada/signals/signal.hpp>
 
 namespace chatterino {
 namespace widgets {
@@ -12,6 +13,7 @@ class TooltipWidget : public BaseWindow
     Q_OBJECT
 public:
     TooltipWidget(BaseWidget *parent = nullptr);
+    ~TooltipWidget();
 
     void setText(QString text);
     void moveTo(QWidget *widget, QPoint point);
@@ -27,11 +29,16 @@ public:
 
 protected:
     virtual void resizeEvent(QResizeEvent *) override;
+    virtual void changeEvent(QEvent *) override;
+    virtual void leaveEvent(QEvent *) override;
+    virtual void dpiMultiplierChanged(float, float) override;
 
 private:
     QLabel *displayText;
+    pajlada::Signals::Connection fontChangedConnection;
 
     void moveIntoDesktopRect(QWidget *parent);
+    void updateFont();
 };
 
 }  // namespace widgets