diff --git a/src/newgrf_gui.cpp b/src/newgrf_gui.cpp
--- a/src/newgrf_gui.cpp
+++ b/src/newgrf_gui.cpp
@@ -1032,8 +1032,9 @@ struct NewGRFWindow : public Window, New
 					if (this->editable && this->active_sel != NULL) SetObjectToPlaceWnd(SPR_CURSOR_MOUSE, PAL_NONE, HT_DRAG, this);
 					break;
 				}
-				/* FALL THROUGH, with double click. */
+				/* With double click, continue */
 			}
+			FALLTHROUGH;
 
 			case WID_NS_REMOVE: { // Remove GRF
 				if (this->active_sel == NULL || !this->editable) break;
@@ -1087,8 +1088,9 @@ struct NewGRFWindow : public Window, New
 					if (this->editable && this->avail_sel != NULL && !HasBit(this->avail_sel->flags, GCF_INVALID)) SetObjectToPlaceWnd(SPR_CURSOR_MOUSE, PAL_NONE, HT_DRAG, this);
 					break;
 				}
-				/* FALL THROUGH, with double click. */
+				/* With double click, continue */
 			}
+			FALLTHROUGH;
 
 			case WID_NS_ADD:
 				if (this->avail_sel == NULL || !this->editable || HasBit(this->avail_sel->flags, GCF_INVALID)) break;
@@ -1225,10 +1227,12 @@ struct NewGRFWindow : public Window, New
 				}
 
 				this->avails.ForceRebuild();
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case GOID_NEWGRF_LIST_EDITED:
 				this->preset = -1;
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case GOID_NEWGRF_PRESET_LOADED: {
 				/* Update scrollbars */
 				int i = 0;