Work around application stuttering on Windows

This is observed by unusual high page faults when the stuttering occurs.
With this workaround, the high page faults still occurs but the GUI remains responsive.

src/app/application.cpp

@@ -847,6 +847,11 @@ void Application::applyMemoryPriority() const
     if (!setProcessInformation)  // only available on Windows >= 8
         return;
 
+    using SETTHREADINFORMATION = BOOL (WINAPI *)(HANDLE, THREAD_INFORMATION_CLASS, LPVOID, DWORD);
+    const auto setThreadInformation = Utils::Misc::loadWinAPI<SETTHREADINFORMATION>(u"Kernel32.dll"_qs, "SetThreadInformation");
+    if (!setThreadInformation)  // only available on Windows >= 8
+        return;
+
 #if (_WIN32_WINNT < _WIN32_WINNT_WIN8)
     // this dummy struct is required to compile successfully when targeting older Windows version
     struct MEMORY_PRIORITY_INFORMATION
@@ -883,6 +888,11 @@ void Application::applyMemoryPriority() const
         break;
     }
     setProcessInformation(::GetCurrentProcess(), ProcessMemoryPriority, &prioInfo, sizeof(prioInfo));
+
+    // To avoid thrashing/sluggishness of the app, set "main event loop" thread to normal memory priority
+    // which is higher/equal than other threads
+    prioInfo.MemoryPriority = MEMORY_PRIORITY_NORMAL;
+    setThreadInformation(::GetCurrentThread(), ThreadMemoryPriority, &prioInfo, sizeof(prioInfo));
 }
 
 void Application::adjustThreadPriority() const