Access-Control-Allow-Origin on chrome extension

You're trying to do cross origin resource sharing (CORS). The bad news is that without a server as a middle man there is no way to do this on a normal web page. The good news is that in a chrome extension you can request permission to access any url's you want. Just put something like this in your manifest.json file.

Allow connections to your site:

 "permissions": [    "http://*.radionsm.lv/"  ],

Allow connections to any site:

 "permissions": [    "http://*/"  ],

When the user installs your extension chrome will inform them of the permissions required in a dialogue box prior to the completion of the install.

Chrome Extensions have two "modes" when making cross-domain XHR requests:

1) If the domain is in the "permissions" section of the manifest.json file - The request doesn't have an "Origin" header, and it always succeeds.

2) If the domain is not in "permissions" - The request includes an "Origin" header with the value "chrome-extension://..." This indicates that the request is a CORS request, and the response must have a valid Access-Control-Allow-Origin header in order to succeed.

https://developer.chrome.com/extensions/xhr

Read through that documentation and check that your permissions have been setup correctly.