Index: hid_cam.c
===================================================================
--- hid_cam.c	(revision 36770)
+++ hid_cam.c	(revision 36771)
@@ -178,6 +178,15 @@
 				}
 			}
 		}
+		for(i = pcb_plug_io_chain; i != NULL; i = i->next) {
+			if (i->alternate_extension != NULL) {
+				int slen = strlen(i->alternate_extension);
+				if (bl > slen && strcmp(buf + bl - slen, i->alternate_extension) == 0) {
+					buf[bl - slen] = 0;
+					break;
+				}
+			}
+		}
 		strcat(buf, suffix);
 	}
 
Index: plug_io.c
===================================================================
--- plug_io.c	(revision 36770)
+++ plug_io.c	(revision 36771)
@@ -389,6 +389,15 @@
 						}
 					}
 				}
+				if (n->alternate_extension != NULL) {
+					int elen = strlen(n->alternate_extension);
+					if ((elen < fn_len) && (strcmp(end-elen, n->alternate_extension) == 0)) {
+						if (n->save_preference_prio > best_score) {
+							best_score = n->save_preference_prio;
+							best = n;
+						}
+					}
+				}
 			}
 			if (best != NULL)
 				return best;
Index: plug_io.h
===================================================================
--- plug_io.h	(revision 36770)
+++ plug_io.h	(revision 36771)
@@ -140,6 +140,7 @@
 	const char *default_fmt;
 	const char *description;
 	const char *default_extension; /* used to generate save-as filename */
+	const char *alternate_extension; /* old/alternative extension, used to generate save-as filename */
 	const char *fp_extension;      /* used to generate save-as filename for footprints */
 	const char *mime_type;