--- /dev/null
+diff -Naur wmmon.app.orig/wmgeneral/wmgeneral.h wmmon.app/wmgeneral/wmgeneral.h
+--- wmmon.app.orig/wmgeneral/wmgeneral.h 1999-06-07 03:09:36.000000000 +0200
++++ wmmon.app/wmgeneral/wmgeneral.h 2020-03-08 12:20:10.345121264 +0100
+@@ -36,7 +36,7 @@
+ /* Global variable */
+ /*******************/
+
+-Display *display;
++extern Display *display;
+
+ /***********************/
+ /* Function Prototypes */
+diff -Naur wmmon.app.orig/wmmon/wmmon.c wmmon.app/wmmon/wmmon.c
+--- wmmon.app.orig/wmmon/wmmon.c 1999-06-07 05:49:45.000000000 +0200
++++ wmmon.app/wmmon/wmmon.c 2020-03-08 12:20:18.657124944 +0100
+@@ -19,6 +19,8 @@
+ int wmmon_mask_width = 64;
+ int wmmon_mask_height = 64;
+
++Display *display;
++
+ void usage(void);
+ void drawstat(int *, int, int, int, int);
+ void wmmon_routine(int, char **);