title: Send message from content script to another
body: <p>I am developping a google chrome extension. My purpose is to send message from my script1.js to script2.js. Here is what i wrote in my manifest.json</p>
  
  <pre><code>  {
      "matches": ["https://www.google.fr/"],
      "css": ["styles.css"],
      "js": ["script1.js"]
  
    },
    {
      "matches": ["my_website.html"],
      "css": ["styles.css"],
      "js": ["script2.js"]
  
    },
  </code></pre>
  
  <p>Here is what i wrote in script1.js:</p>
  
  <blockquote>
    <p>chrome.runtime.sendMessage('hello world!!!!!!');</p>
  </blockquote>
  
  <p>and in script2.js:</p>
  
  <blockquote>
    <p>chrome.runtime.onMessage.addListener(function(response,sender,sendResponse){</p>
    
    <p>alert(response);</p>
    
    <p>} );</p>
  </blockquote>
  
  <p>I don't think i'm doing it the write way, i think i've to use the background.js but i don't know how. </p>
  
  <p>Thanks very much in advance.</p>