Question

My mouse has two buttons on the side, whose default behaviour are “Back” and “Forward”.

What I’d like to know is whether or not it’s possible to detect clicks of these mouse buttons in JavaScript, or if these are “special” buttons akin to the keyboard’s “Play”, “Volume Up” and “Wireless on/off” buttons.

Answer 1

I am not aware of any specific mouse events.

You can, however, easily find out yourself by inspecting the event object of the mousedown event. Fullscreen fiddle: http://jsfiddle.net/dWfDL/1/show/

var text = typeof document.body.textContent != "undefined" ? "textContent" : "innerText";
window.onmousedown = function(e){
    //Inspect the `e` object, for example using a for(var i in e) loop, or:
    //console.log(e);
    var s = [];
    for(var i in e){
        try{
            if(e[i] !== null){
                if(i.toUpperCase() == i) continue; //Ignore constants
                if(typeof e[i] == "function") continue; //Ignore functions
                if(e[i].parentNode) continue; //Ignore elements
                if(e[i] === window) continue; //Ignore Window
            }
            s.push(i + " =\t\t" + e[i]);
        }catch(err){s.push(i + " \tERROR reading property.")}
    }
    e.preventDefault();
    s = s.join("\n") + "\n\n";
    document.body[text] = s + document.body[text];
}
//Double-click to wipe contents
window.ondblclick = function(){
    document.body[text] = "";
}