diff --git a/dll/win32/kernel32/client/proc.c b/dll/win32/kernel32/client/proc.c
index 9b680eb533..9d64e2176a 100644
--- a/dll/win32/kernel32/client/proc.c
+++ b/dll/win32/kernel32/client/proc.c
@@ -2446,6 +2446,13 @@ CreateProcessInternalW(IN HANDLE hUserToken,
         return FALSE;
     }
 
+    /* This fixes the 3D screen saver locking up the desktop CORE-8217 */
+    if (dwCreationFlags == 0)
+    {
+        dwCreationFlags |= IDLE_PRIORITY_CLASS;
+        DPRINT("Setting IDLE_PRIORITY_CLASS for '%S/%S'.\n", lpApplicationName, lpCommandLine);
+    }
+
     /* Convert the priority class */
     if (dwCreationFlags & IDLE_PRIORITY_CLASS)
     {