Firefox doesn't set content type correctly if set in the headers object.

[blainekasten]

Given the following code:

reqwest({
    url: '/test',
    method: 'PUT',
    data: JSON.stringify({obj: true}),
    headers: {
        'Content-Type': 'application/json'
    }
});

This properly sets the content-type in chrome. But not in firefox. Thus, the server will improperly parse the params. It works fine if I set the contentType: 'application/json'. So you should look at both locations to set the header.