$.getJSON – ajax is sent but callback function is ignored – Internet Explorer-Collection of common programming errors

As it fails in specific browsers, it’s likely that it is a combination of unexpected headers in the response, and how the browser handles the data based on that.

If for example the response has the content type text/html instead of application/json, the browser might try to turn the response content into a HTML document (by adding pre tags around it), which would then cause the JSON parsing to fail.

If you use the $.ajax method, you can also catch any error message, which would give you a clue to what’s going on:

$.ajax({
  url: addr,
  dataType: 'json',
  success: function(data){
    alert('whoooo working'); //