diff --git a/applications/fetcher/About.okm b/applications/fetcher/About.okm
index 2948fba..3589a89 100644
--- a/applications/fetcher/About.okm
+++ b/applications/fetcher/About.okm
@@ -2,7 +2,7 @@ MODULE About;
     IMPORT OS;
 
     VAR aboutRunning: CHAR;
-        aboutWindow: ARRAY 36 OF CHAR;
+        aboutWindow: ARRAY WINDOW_STRUCT_SIZE OF CHAR;
 
     PROCEDURE AboutMain();
     BEGIN
diff --git a/applications/fetcher/Browser.okm b/applications/fetcher/Browser.okm
index 5403486..0561825 100644
--- a/applications/fetcher/Browser.okm
+++ b/applications/fetcher/Browser.okm
@@ -2,7 +2,7 @@ MODULE Browser;
     IMPORT OS, About, Desktop;
 
     VAR browserRunning: CHAR;
-        browserWindow: ARRAY 36 OF CHAR;
+        browserWindow: ARRAY WINDOW_STRUCT_SIZE OF CHAR;
         browserIcons: ARRAY 12 OF Fox32OSButtonWidget;
         browserPage: INT;
         browserNumberOfPages: INT;
diff --git a/applications/fetcher/Desktop.okm b/applications/fetcher/Desktop.okm
index d651dec..7a75471 100644
--- a/applications/fetcher/Desktop.okm
+++ b/applications/fetcher/Desktop.okm
@@ -2,7 +2,7 @@ MODULE Desktop;
     IMPORT OS;
 
     VAR desktopRunning: CHAR;
-        desktopWindow: ARRAY 36 OF CHAR;
+        desktopWindow: ARRAY WINDOW_STRUCT_SIZE OF CHAR;
         desktopIcons: ARRAY 5 OF Fox32OSButtonWidget;
 
     EXTERN diskIcon: ARRAY 1024 OF INT;
diff --git a/applications/fetcher/OS.okm b/applications/fetcher/OS.okm
index 8351f31..66f3950 100644
--- a/applications/fetcher/OS.okm
+++ b/applications/fetcher/OS.okm
@@ -1,6 +1,8 @@
 (* FIXME: this module should probably be moved somewhere global so all applications can use it *)
 
 MODULE OS;
+    CONST WINDOW_STRUCT_SIZE = 36;
+
     EXTERN PROCEDURE new_window, destroy_window, draw_str_to_overlay, get_window_overlay_number,
         draw_widgets_to_window, draw_filled_rectangle_to_overlay, GetNextWindowEvent, DrawPixel,
         save_state_and_yield_task, start_dragging_window, handle_widget_click, fill_window, fill_overlay,