diff --git a/src/gfxinit.cpp b/src/gfxinit.cpp
index b6aa3888bf..f87b10391e 100644
--- a/src/gfxinit.cpp
+++ b/src/gfxinit.cpp
@@ -153,6 +153,7 @@ static std::unique_ptr<GRFConfig> GetDefaultExtraGRFConfig()
 	gc->palette |= GRFP_GRF_DOS;
 	FillGRFDetails(*gc, false, BASESET_DIR);
 	gc->flags.Reset(GRFConfigFlag::InitOnly);
+	gc->flags.Set(GRFConfigFlag::System);
 	return gc;
 }
 
@@ -165,6 +166,7 @@ static std::unique_ptr<GRFConfig> GetBasesetExtraGRFConfig()
 	auto gc = std::make_unique<GRFConfig>(BaseGraphics::GetUsedSet()->GetOrCreateExtraConfig());
 	if (gc->param.empty()) gc->SetParameterDefaults();
 	gc->flags.Reset(GRFConfigFlag::InitOnly);
+	gc->flags.Set(GRFConfigFlag::System);
 	return gc;
 }
 
diff --git a/src/newgrf/newgrf_actd.cpp b/src/newgrf/newgrf_actd.cpp
index 8231c9a192..ac00209d8d 100644
--- a/src/newgrf/newgrf_actd.cpp
+++ b/src/newgrf/newgrf_actd.cpp
@@ -319,7 +319,7 @@ static void ParamSet(ByteReader &buf)
 				/* Disable the read GRF if it is a static NewGRF. */
 				DisableStaticNewGRFInfluencingNonStaticNewGRFs(*c);
 				src1 = 0;
-			} else if (file == nullptr || c == nullptr || c->status == GCS_DISABLED) {
+			} else if (file == nullptr || c == nullptr || c->status == GCS_DISABLED || c->flags.Test(GRFConfigFlag::System)) {
 				src1 = 0;
 			} else if (src1 == 0xFE) {
 				src1 = c->version;