diff --git a/filter/kyofilter b/filter/kyofilter
index 5045a7c..2fbb99d 100755
--- a/filter/kyofilter
+++ b/filter/kyofilter
@@ -34,7 +34,7 @@ def process_stream(lines, account_code):
 
     for line in lines:
         stripped = line.rstrip(b'\r\n')
-        if not injected and (stripped == b'%%EndSetup' or stripped.startswith(b'%%Page:')):
+        if not injected and (stripped.rstrip() == b'%%EndSetup' or stripped.startswith(b'%%Page:')):
             yield inject
             injected = True
         yield line
diff --git a/tests/test_kyofilter.py b/tests/test_kyofilter.py
index dc66f2c..10f6269 100644
--- a/tests/test_kyofilter.py
+++ b/tests/test_kyofilter.py
@@ -79,3 +79,9 @@ class TestProcessStream:
         ps = "%!PS\n%%BeginSetup\n%%EndSetup\nshowpage\n"
         result = self._collect(ps, "00012345")
         assert b"showpage\n" in result
+
+    def test_warns_when_no_injection_point(self, capsys):
+        ps = "%!PS\nshowpage\n"
+        self._collect(ps, "00012345")
+        captured = capsys.readouterr()
+        assert "WARNING" in captured.err