use QMetaObject::invokeMethod to post to thread (#6203)

src/util/PostToThread.hpp

@@ -3,34 +3,13 @@
 #include "debug/AssertInGuiThread.hpp"
 
 #include <QCoreApplication>
+#include <QMetaObject>
 
 namespace chatterino {
 
-// Taken from
-// https://stackoverflow.com/questions/21646467/how-to-execute-a-functor-or-a-lambda-in-a-given-thread-in-qt-gcd-style
-// Qt 5/4 - preferred, has least allocations
 static void postToThread(auto &&f, QObject *obj = QCoreApplication::instance())
 {
-    struct Event : public QEvent {
-        using Fun = typename std::decay_t<decltype(f)>;
-        Fun fun;
-
-        Event(decltype(fun) f)
-            : QEvent(QEvent::None)
-            , fun(std::forward<decltype(fun)>(f))
-        {
-        }
-        Event(const Event &) = delete;
-        Event(Event &&) = delete;
-        Event &operator=(const Event &) = delete;
-        Event &operator=(Event &&) = delete;
-
-        ~Event() override
-        {
-            fun();
-        }
-    };
-    QCoreApplication::postEvent(obj, new Event(std::forward<decltype(f)>(f)));
+    QMetaObject::invokeMethod(obj, std::forward<decltype(f)>(f));
 }
 
 static void runInGuiThread(auto &&fun)