Execution order of multiple setTimeout() functions with same interval

The Spec is here.

My interpretation of setTimeout step 8 in section 7.3 is that the execution order is supposed to be guaranteed.

However, I investigated this issue because when the window is minimized and then maximised in Chrome, I was finding that timeouts set in events coming from external sources (like websockets or webworkers) were being executed in the wrong order. I assume this is a browser bug and will hopefully be fixed soon.

Play around with this in your fiddle

$(document).ready(function() {
    setTimeout(function() {
        $("#output").append(" one ");
    }, 1000);
});
$(document).ready(function() {
    setTimeout(function() {
        $("#output").append(" two ");
    }, 999);
});​

And you will see that both

output: one two
output: two one

are possible. So Speransky is right that you cannot rely on your timeouts executing in the same order always.

Note that I have change one time with 1ms to show that the timeout 1000ms can execute before the 999ms timeout.

EDIT: The below code can delay execution without any chance of two to be printed before one

function(){
    setTimeout(function() {
        $("#output").append(" one ");
       setTimeout(function() {
           $("#output").append(" two ");
       }, 100);
    }, 1000);
}