diff --git a/internal/client/chrome_test.go b/internal/client/chrome_test.go
new file mode 100644
index 0000000..763e059
--- /dev/null
+++ b/internal/client/chrome_test.go
@@ -0,0 +1,46 @@
+package client
+
+import (
+	"encoding/hex"
+	"testing"
+)
+
+func TestMakeGREASE(t *testing.T) {
+	a := hex.EncodeToString(makeGREASE())
+	if a[1] != 'a' || a[3] != 'a' {
+		t.Errorf("GREASE got %v", a)
+	}
+
+	var GREASEs []string
+	for i := 0; i < 50; i++ {
+		GREASEs = append(GREASEs, hex.EncodeToString(makeGREASE()))
+	}
+	var eqCount int
+	for _, g := range GREASEs {
+		if a == g {
+			eqCount++
+		}
+	}
+	if eqCount > 40 {
+		t.Error("GREASE is not random", GREASEs)
+	}
+}
+
+func TestComposeExtension(t *testing.T) {
+	serverName := "cdn.bizible.com"
+	keyShare, _ := hex.DecodeString("010a8896b68fb16e2a245ed87be2699348ab72068bb326eac5beaa00fa56ff17")
+
+	result := (&Chrome{}).composeExtensions(serverName, keyShare)
+	target, _ := hex.DecodeString("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")
+	for p := 0; p < len(result); {
+		// skip GREASEs
+		if p == 0 || p == 43 || p == 122 || p == 174 || p == 191 {
+			p += 2
+			continue
+		}
+		if result[p] != target[p] {
+			t.Errorf("inequality at %v", p)
+		}
+		p += 1
+	}
+}
diff --git a/internal/client/state_test.go b/internal/client/state_test.go
index 85f32e5..4939f73 100644
--- a/internal/client/state_test.go
+++ b/internal/client/state_test.go
@@ -6,9 +6,9 @@ import (
 )
 
 func TestSSVtoJson(t *testing.T) {
-	ssv := "UID=iGAO85zysIyR4c09CyZSLdNhtP/ckcYu7nIPI082AHA=;PublicKey=IYoUzkle/T/kriE+Ufdm7AHQtIeGnBWbhhlTbmDpUUI=;ServerName=www.bing.com;TicketTimeHint=3600;NumConn=4;MaskBrowser=chrome;"
+	ssv := "UID=iGAO85zysIyR4c09CyZSLdNhtP/ckcYu7nIPI082AHA=;PublicKey=IYoUzkle/T/kriE+Ufdm7AHQtIeGnBWbhhlTbmDpUUI=;ServerName=www.bing.com;NumConn=4;MaskBrowser=chrome;"
 	json := ssvToJson(ssv)
-	expected := []byte(`{"UID":"iGAO85zysIyR4c09CyZSLdNhtP/ckcYu7nIPI082AHA=","PublicKey":"IYoUzkle/T/kriE+Ufdm7AHQtIeGnBWbhhlTbmDpUUI=","ServerName":"www.bing.com","TicketTimeHint":3600,"NumConn":4,"MaskBrowser":"chrome"}`)
+	expected := []byte(`{"UID":"iGAO85zysIyR4c09CyZSLdNhtP/ckcYu7nIPI082AHA=","PublicKey":"IYoUzkle/T/kriE+Ufdm7AHQtIeGnBWbhhlTbmDpUUI=","ServerName":"www.bing.com","NumConn":4,"MaskBrowser":"chrome"}`)
 	if !bytes.Equal(expected, json) {
 		t.Error(
 			"For", "ssvToJson",