diff --git a/src/p_map.cpp b/src/p_map.cpp
index e36cb9316..4d30246f3 100644
--- a/src/p_map.cpp
+++ b/src/p_map.cpp
@@ -4460,7 +4460,7 @@ AActor *P_LinePickActor(AActor *t1, angle_t angle, fixed_t distance, int pitch,
 	TData.hitGhosts = true;
 	
 	if (Trace(t1->X(), t1->Y(), shootz, t1->Sector, vx, vy, vz, distance,
-		actorMask, wallMask, t1, trace, TRACE_NoSky, CheckForActor, &TData))
+		actorMask, wallMask, t1, trace, TRACE_NoSky | TRACE_PortalRestrict, CheckForActor, &TData))
 	{
 		if (trace.HitType == TRACE_HitActor)
 		{
diff --git a/src/p_trace.h b/src/p_trace.h
index 55447e021..ef082f788 100644
--- a/src/p_trace.h
+++ b/src/p_trace.h
@@ -84,6 +84,7 @@ enum
 	TRACE_NoSky			= 1,	// Hitting the sky returns TRACE_HitNone
 	TRACE_PCross		= 2,	// Trigger SPAC_PCROSS lines
 	TRACE_Impact		= 4,	// Trigger SPAC_IMPACT lines
+	TRACE_PortalRestrict= 8,	// Cannot go through portals without a static link offset.
 };
 
 // return values from callback
diff --git a/src/thingdef/thingdef_codeptr.cpp b/src/thingdef/thingdef_codeptr.cpp
index 5f518fab0..98dd60f2d 100644
--- a/src/thingdef/thingdef_codeptr.cpp
+++ b/src/thingdef/thingdef_codeptr.cpp
@@ -3870,7 +3870,7 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_CheckLOF)
 	lof_data.Flags = flags;
 	lof_data.BadActor = false;
 
-	Trace(pos.x, pos.y, pos.z, sec, vx, vy, vz, range, ActorFlags::FromInt(0xFFFFFFFF), ML_BLOCKEVERYTHING, self, trace, 0,
+	Trace(pos.x, pos.y, pos.z, sec, vx, vy, vz, range, ActorFlags::FromInt(0xFFFFFFFF), ML_BLOCKEVERYTHING, self, trace, TRACE_PortalRestrict,
 		CheckLOFTraceFunc, &lof_data);
 
 	if (trace.HitType == TRACE_HitActor ||