diff -Naur algol68g-2.8.4-old/source/plotutils.c algol68g-2.8.4-new/source/plotutils.c
--- algol68g-2.8.4-old/source/plotutils.c	2016-10-11 18:14:48.000000000 -0300
+++ algol68g-2.8.4-new/source/plotutils.c	2021-07-30 02:42:29.762627511 -0300
@@ -1026,10 +1026,10 @@
     X_COORD (&DEVICE (f)) = 0;
     Y_COORD (&DEVICE (f)) = 0;
     return (PLOTTER (&DEVICE (f)));
-  } else if (!strcmp (device_type, "gif")) {
-/*------------------------------------+
-| Supported plotter type - pseudo GIF |
-+------------------------------------*/
+  } else if (!strcmp (device_type, "gif") || !strcmp (device_type, "png")) {
+/*-------------------------------------------+
+| Supported plotter type - pseudo GIF or PNG |
++-------------------------------------------*/
     char *z = DEREF (char, &A68_PAGE_SIZE (&DEVICE (f))), size[BUFFER_SIZE];
 /* Establish page size */
     if (!scan_int (&z, &(WINDOW_X_SIZE (&DEVICE (f))))) {
@@ -1067,7 +1067,7 @@
     (void) pl_setplparam (PLOTTER_PARAMS (&DEVICE (f)), "BITMAPSIZE", size);
     (void) pl_setplparam (PLOTTER_PARAMS (&DEVICE (f)), "BG_COLOR", (void *) "black");
     (void) pl_setplparam (PLOTTER_PARAMS (&DEVICE (f)), "GIF_ANIMATION", (void *) "no");
-    PLOTTER (&DEVICE (f)) = pl_newpl_r ("gif", NULL, STREAM (&DEVICE (f)), stderr, PLOTTER_PARAMS (&DEVICE (f)));
+    PLOTTER (&DEVICE (f)) = pl_newpl_r (device_type, NULL, STREAM (&DEVICE (f)), stderr, PLOTTER_PARAMS (&DEVICE (f)));
     if (PLOTTER (&DEVICE (f)) == NULL) {
       diagnostic_node (A68_RUNTIME_ERROR, p, ERROR_DEVICE_CANNOT_OPEN);
       exit_genie (p, A68_RUNTIME_ERROR);