fix return

caddywebp.go

@@ -3,11 +3,6 @@ package caddywebp
 import (
 	"bytes"
 	"fmt"
-	"github.com/caddyserver/caddy/v2"
-	"github.com/caddyserver/caddy/v2/caddyconfig/httpcaddyfile"
-	"github.com/caddyserver/caddy/v2/modules/caddyhttp"
-	"github.com/chai2010/webp"
-	"golang.org/x/image/bmp"
 	"image"
 	"image/gif"
 	"image/jpeg"
@@ -18,6 +13,12 @@ import (
 	"os"
 	"path"
 	"strings"
+
+	"github.com/caddyserver/caddy/v2"
+	"github.com/caddyserver/caddy/v2/caddyconfig/httpcaddyfile"
+	"github.com/caddyserver/caddy/v2/modules/caddyhttp"
+	"github.com/chai2010/webp"
+	"golang.org/x/image/bmp"
 )
 
 const Quality = 80
@@ -109,8 +110,9 @@ func (s Webp) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.H
 	case "image/gif":
 		decoder = decodeGif
 	default:
-		next.ServeHTTP(w, r)
+		return next.ServeHTTP(w, r)
 	}
+	
 	img, err := decoder(bytes.NewReader(resp.Body.Bytes()))
 	if err != nil || img == nil {
 		log.Println(err)