func (h *Handler) DefaultErrorHandler(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
	h.L.Warnln("A client requested the default error URL, environment variable OAUTH2_ERROR_URL is probably not set.")

	t, err := template.New("consent").Parse(`
<html>
<head>
	<title>An OAuth 2.0 Error Occurred</title>
</head>
<body>
<h1>
	The OAuth2 request resulted in an error.
</h1>
<ul>
	<li>Error: {{ .Name }}</li>
	<li>Description: {{ .Description }}</li>
	<li>Hint: {{ .Hint }}</li>
	<li>Debug: {{ .Debug }}</li>
</ul>
<p>
	You are seeing this default error page because the administrator has not set a dedicated error URL (environment variable <code>OAUTH2_ERROR_URL</code> is not set). 
	If you are an administrator, please read <a href="https://www.ory.sh/docs">the guide</a> to understand what you
	need to do. If you are a user, please contact the administrator.
</p>
</body>
</html>
`)
	if err != nil {
		h.H.WriteError(w, r, err)
		return
	}

	if err := t.Execute(w, struct {
		Name        string
		Description string
		Hint        string
		Debug       string
	}{
		Name:        r.URL.Query().Get("error"),
		Description: r.URL.Query().Get("error_description"),
		Hint:        r.URL.Query().Get("error_hint"),
		Debug:       r.URL.Query().Get("error_debug"),
	}); err != nil {
		h.H.WriteError(w, r, err)
		return
	}
}
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.