diff --git a/Makefile b/Makefile
index bd01bff..c80f5da 100644
--- a/Makefile
+++ b/Makefile
@@ -12,7 +12,7 @@ EXTERNAL_SERVICES:=1
 
 SCDOC=scdoc
 
-.PHONY: install shellcheck
+.PHONY: install test shellcheck test_legacy_nerdfont
 
 VERSION:=1.13.0
 
@@ -33,11 +33,17 @@ docs/%: docs/%.scd
 
 all: $(PROGRAMS) $(DOCS)
 
-test: shellcheck
+test: shellcheck test_legacy_nerdfont
 
 shellcheck:
 	find . -type f -name '*.sh' -print0 | xargs -0 shellcheck -x --shell=sh
 
+test_legacy_nerdfont: programs/test_legacy_nerdfont
+	programs/test_legacy_nerdfont < configs/default_hooks/sxmo_hook_icons.sh
+
+programs/test_legacy_nerdfont: programs/test_legacy_nerdfont.c
+	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) -o $@ $< $(shell pkg-config --cflags --libs icu-io)
+
 programs/%: programs/%.c
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) -o $@ $<
 
diff --git a/programs/test_legacy_nerdfont.c b/programs/test_legacy_nerdfont.c
new file mode 100644
index 0000000..272b2c9
--- /dev/null
+++ b/programs/test_legacy_nerdfont.c
@@ -0,0 +1,32 @@
+#include <unicode/ustdio.h>
+#include <unicode/ubidi.h>
+
+int main() {
+	UFILE *in = u_finit(stdin, NULL, NULL);
+	int line = 1;
+	int err = 0;
+	bool comment = false;
+
+	while (true) {
+		UChar chr = u_fgetc(in);
+		if (chr == U_EOF) {
+			break;
+		} if (chr == '\n') {
+			line++;
+			comment = false;
+			continue;
+		} if (chr == '#') {
+			comment = true;
+		}
+
+		if (comment)
+			continue;
+
+		if (chr >= 0xF900 && chr <= 0xFDFF) {
+			u_printf("ERROR: detected legacy nerd font icon in wrong characer range: \"%C\" 0x%x on line %d\n", chr, chr, line);
+			err = 1;
+		}
+	}
+
+	return err;
+}