diff --git a/src/autoreplace_gui.cpp b/src/autoreplace_gui.cpp
--- a/src/autoreplace_gui.cpp
+++ b/src/autoreplace_gui.cpp
@@ -535,6 +535,7 @@ static const NWidgetPart _nested_replace
 		NWidget(WWT_CLOSEBOX, COLOUR_GREY),
 		NWidget(WWT_CAPTION, COLOUR_GREY, WID_RV_CAPTION), SetDataTip(STR_REPLACE_VEHICLES_WHITE, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
 		NWidget(WWT_SHADEBOX, COLOUR_GREY),
+		NWidget(WWT_DEFSIZEBOX, COLOUR_GREY),
 		NWidget(WWT_STICKYBOX, COLOUR_GREY),
 	EndContainer(),
 	NWidget(NWID_HORIZONTAL, NC_EQUALSIZE),
@@ -575,6 +576,7 @@ static const NWidgetPart _nested_replace
 		NWidget(WWT_CLOSEBOX, COLOUR_GREY),
 		NWidget(WWT_CAPTION, COLOUR_GREY, WID_RV_CAPTION), SetMinimalSize(433, 14), SetDataTip(STR_REPLACE_VEHICLES_WHITE, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
 		NWidget(WWT_SHADEBOX, COLOUR_GREY),
+		NWidget(WWT_DEFSIZEBOX, COLOUR_GREY),
 		NWidget(WWT_STICKYBOX, COLOUR_GREY),
 	EndContainer(),
 	NWidget(NWID_HORIZONTAL, NC_EQUALSIZE),