JavaScript console.log causes error: “Synchronous XMLHttpRequest on the main thread is deprecated…”

Question

I have been adding logs to the console to check the status of different variables without using the Firefox debugger.

However, in many places in which I add a

Answer 1

Visual Studio 2015/2017's live debugger is injecting code that contains the deprecated call.

Answer 2

1. In Chrome, press F12
2. Develomping tools-> press F1.
3. See settings->general->Apperance: "Don't show chrome Data Saver warning"- set this checkbox.
4. See settings->general->Console: "Log XMLHTTPRequest" - set this checkbox too.

Enjoy

Answer 3

To avoid this warning, do not use:

async: false

in any of your $.ajax() calls. This is the only feature of XMLHttpRequest that's deprecated.

The default is

async: true

jQuery has deprecated synchronous XMLHTTPRequest

Answer 4

And I got this exception for including one can.js script inside another, e.g.,

{{>anotherScript}}

Answer 5

I got this exception when I set url in query like "example.com/files/text.txt". Ive changed url to "http://example.com/files/text.txt" and this exception dissapeared.

Answer 6

I have been looking at the answers all impressive. I think He should provide the code that is giving him a problem. Given the example below, If you have a script to link to jquery in page.php then you get that notice.

$().ready(function () {
    $.ajax({url: "page.php",
        type: 'GET',
        success: function (result) {
        $("#page").html(result);
   }});
 });