What's query string limit in node.js openurl and how to send email using default email client?

I'm using node.js for my desktop app. I need to send email from it. So I use the below code:

require("openurl").open("mailto:"+emailAddress+"?" + 
    "subject=TEST subject&" +
    "body=Hello! How are you?\nHello! How are you?\nHello! How are you?\nHello! " + 
    "How are you?\nHello! How are you?\nHello! How are you?\nHello! How are you?\n" +
    "Hello! How are you?\nHello! How are you?\nHello! How are you?\n");

This invokes the email client, but the email body text is truncated by around 200 characters.

I tried the below code also:

require("openurl").mailto(["john@example.com", "jane@example.com"],
        { subject: "Hello!", body: "This is\na generated email!\n" });

Reference link: https://github.com/rauschma/openurl

This code just adds the email id (first email) and nothing else (subject and email body doesn't get added).