diff --git a/misc_gui.c b/misc_gui.c
--- a/misc_gui.c
+++ b/misc_gui.c
@@ -372,7 +372,7 @@ void ShowBuildTreesScenToolbar()
 	AllocateWindowDescFront(&_build_trees_scen_desc, 0);
 }
 
-static uint32 _errmsg_decode_params[10];
+static uint32 _errmsg_decode_params[20];
 static StringID _errmsg_message_1, _errmsg_message_2;
 static uint _errmsg_duration;
 
diff --git a/widget.c b/widget.c
--- a/widget.c
+++ b/widget.c
@@ -146,7 +146,7 @@ void DrawWindowWidgets(Window *w)
 	const Widget *wi;
 	DrawPixelInfo *dpi = _cur_dpi;
 	Rect r;
-	uint32 dparam_backup[10];
+	uint32 dparam_backup[20];
 	uint32 cur_click, cur_disabled, cur_hidden;
 
 	if (w->desc_flags & WDF_RESTORE_DPARAM)	COPY_OUT_DPARAM(dparam_backup, 0, lengthof(dparam_backup));