diff --git a/src/common/platform/posix/i_system.h b/src/common/platform/posix/i_system.h
index 4d800d53b3..5573e26d32 100644
--- a/src/common/platform/posix/i_system.h
+++ b/src/common/platform/posix/i_system.h
@@ -54,17 +54,6 @@ bool I_WriteIniFailed (const char* filename);
 class FGameTexture;
 bool I_SetCursor(FGameTexture *);
 
-static inline char *strlwr(char *str)
-{
-	char *ptr = str;
-	while(*ptr)
-	{
-		*ptr = tolower(*ptr);
-		++ptr;
-	}
-	return str;
-}
-
 inline int I_GetNumaNodeCount() { return 1; }
 inline int I_GetNumaNodeThreadCount(int numaNode) { return std::max<int>(std::thread::hardware_concurrency(), 1); }
 inline void I_SetThreadNumaNode(std::thread &thread, int numaNode) { }
diff --git a/src/scripting/decorate/thingdef_parse.cpp b/src/scripting/decorate/thingdef_parse.cpp
index 19c8f38ab6..03a249814d 100644
--- a/src/scripting/decorate/thingdef_parse.cpp
+++ b/src/scripting/decorate/thingdef_parse.cpp
@@ -49,9 +49,6 @@
 #include "v_text.h"
 #include "m_argv.h"
 #include "v_video.h"
-#ifndef _MSC_VER
-#include "i_system.h"  // for strlwr()
-#endif // !_MSC_VER
 
 void ParseOldDecoration(FScanner &sc, EDefinitionType def, PNamespace *ns);
 EXTERN_CVAR(Bool, strictdecorate);
@@ -945,15 +942,12 @@ static void ParseActorProperty(FScanner &sc, Baggage &bag)
 		"Spawn", "See", "Melee", "Missile", "Pain", "Death", "XDeath", "Burn", 
 		"Ice", "Raise", "Crash", "Crush", "Wound", "Disintegrate", "Heal", NULL };
 
-	strlwr (sc.String);
-
 	FString propname = sc.String;
 
 	if (sc.CheckString ("."))
 	{
 		sc.MustGetString ();
 		propname += '.';
-		strlwr (sc.String);
 		propname += sc.String;
 	}
 	else
diff --git a/src/scripting/decorate/thingdef_states.cpp b/src/scripting/decorate/thingdef_states.cpp
index 570905741a..d518d67691 100644
--- a/src/scripting/decorate/thingdef_states.cpp
+++ b/src/scripting/decorate/thingdef_states.cpp
@@ -45,9 +45,6 @@
 #include "thingdef.h"
 #include "codegen.h"
 #include "backend/codegen_doom.h"
-#ifndef _MSC_VER
-#include "i_system.h"  // for strlwr()
-#endif // !_MSC_VER
 
 //==========================================================================
 //***
@@ -562,11 +559,8 @@ FxExpression *ParseActions(FScanner &sc, FState state, FString statestring, Bagg
 
 FxExpression* ParseAction(FScanner &sc, FState state, FString statestring, Baggage &bag)
 {
-	// Make the action name lowercase
-	strlwr (sc.String);
-
 	FxExpression *call = DoActionSpecials(sc, state, bag);
-	if (call != NULL)
+	if (call != nullptr)
 	{
 		return call;
 	}