diff --git a/Makefile b/Makefile
index 13f1717b0a..2b788d7885 100644
--- a/Makefile
+++ b/Makefile
@@ -79,7 +79,7 @@ SELECTED_FLAGS = AC AD AE AF AG AI AL AM AO AQ AR AS AT AU AW AX AZ \
 	XK \
 	YE YT \
 	ZA ZM ZW \
-        GB-ENG GB-SCT GB-WLS
+	GB-ENG GB-SCT GB-WLS
 
 ifeq (,$(shell which $(ZOPFLIPNG)))
   ifeq (,$(wildcard $(ZOPFLIPNG)))