diff --git a/mitmproxy/contentviews.py b/mitmproxy/contentviews.py
index 68d3d9590..304b52411 100644
--- a/mitmproxy/contentviews.py
+++ b/mitmproxy/contentviews.py
@@ -389,7 +389,7 @@ class ViewJavaScript(View):
     def __call__(self, data, **metadata):
         opts = jsbeautifier.default_options()
         opts.indent_size = 2
-        res = jsbeautifier.beautify(data.decode(), opts)
+        res = jsbeautifier.beautify(strutils.native(data), opts)
         return "JavaScript", format_text(res)