diff --git a/src/common/platform/win32/i_input.cpp b/src/common/platform/win32/i_input.cpp
index c058cdfa9..33201872c 100644
--- a/src/common/platform/win32/i_input.cpp
+++ b/src/common/platform/win32/i_input.cpp
@@ -128,6 +128,7 @@ EXTERN_CVAR(Bool, i_pauseinbackground);
 
 
 CVAR (Bool, k_allowfullscreentoggle, true, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
+CVAR (Bool, i_allowprioritychange, true, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 
 static void I_CheckGUICapture ()
 {
@@ -485,13 +486,16 @@ LRESULT CALLBACK WndProc (HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
 
 	case WM_ACTIVATEAPP:
 		AppActive = (wParam == TRUE);
-		if (wParam || !i_pauseinbackground)
+		if (!i_pauseinbackground && i_allowprioritychange)
 		{
-			SetPriorityClass (GetCurrentProcess (), INGAME_PRIORITY_CLASS);
-		}
-		else if (!noidle && !(sysCallbacks.NetGame && sysCallbacks.NetGame()))
-		{
-			SetPriorityClass (GetCurrentProcess (), IDLE_PRIORITY_CLASS);
+			if (wParam)
+			{
+				SetPriorityClass (GetCurrentProcess (), INGAME_PRIORITY_CLASS);
+			}
+			else if (!noidle && !(sysCallbacks.NetGame && sysCallbacks.NetGame()))
+			{
+				SetPriorityClass (GetCurrentProcess (), IDLE_PRIORITY_CLASS);
+			}
 		}
 		S_SetSoundPaused (wParam);
 		break;
diff --git a/src/common/platform/win32/i_system.cpp b/src/common/platform/win32/i_system.cpp
index a2b48dda7..e2e3736e6 100644
--- a/src/common/platform/win32/i_system.cpp
+++ b/src/common/platform/win32/i_system.cpp
@@ -243,6 +243,9 @@ void CalculateCPUSpeed()
         // probably never use the performance statistics.
         min_diff = freq.LowPart * 11 / 200;
 
+		// just in case we were launched with a custom priority class, keep it
+		DWORD OldPriorityClass = GetPriorityClass(GetCurrentProcess());
+
 		// Minimize the chance of task switching during the testing by going very
 		// high priority. This is another reason to avoid timing for too long.
 		SetPriorityClass(GetCurrentProcess(), REALTIME_PRIORITY_CLASS);
@@ -257,7 +260,7 @@ void CalculateCPUSpeed()
 		do { QueryPerformanceCounter(&count1); } while ((count1.QuadPart - count2.QuadPart) < min_diff);
 		ClockCalibration.Unclock();
 
-		SetPriorityClass(GetCurrentProcess(), NORMAL_PRIORITY_CLASS);
+		SetPriorityClass(GetCurrentProcess(), OldPriorityClass);
 		SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_NORMAL);
 
 		PerfToSec = double(count1.QuadPart - count2.QuadPart) / (double(ClockCalibration.GetRawCounter()) * freq.QuadPart);
diff --git a/wadsrc/static/zscript/actors/actor.zs b/wadsrc/static/zscript/actors/actor.zs
index 94e95e86e..7293205df 100644
--- a/wadsrc/static/zscript/actors/actor.zs
+++ b/wadsrc/static/zscript/actors/actor.zs
@@ -1302,7 +1302,7 @@ class Actor : Thinker native
 	native bool A_SetSize(double newradius = -1, double newheight = -1, bool testpos = false);
 	native void A_SprayDecal(String name, double dist = 172, vector3 offset = (0, 0, 0), vector3 direction = (0, 0, 0), bool useBloodColor = false, color decalColor = 0, TranslationID translation = 0);
 	native void A_SetMugshotState(String name);
-	native void CopyBloodColor(Actor other);
+	native void CopyBloodColor(readonly<Actor> other);
 
 	native void A_RearrangePointers(int newtarget, int newmaster = AAPTR_DEFAULT, int newtracer = AAPTR_DEFAULT, int flags=0);
 	native void A_TransferPointer(int ptr_source, int ptr_recipient, int sourcefield, int recipientfield=AAPTR_DEFAULT, int flags=0);