Three.js Resizing Canvas

So the canvas element can be resized like every other element. What you want to do is tell the render and camera to resize the contents of your canvas as well.

window.addEventListener( 'resize', onWindowResize, false );

function onWindowResize(){

    camera.aspect = window.innerWidth / window.innerHeight;
    camera.updateProjectionMatrix();

    renderer.setSize( window.innerWidth, window.innerHeight );

}

Finally the problem were solved the actually problem was coming from because the application is using the THREE.EffectComposer object, in the class constructor a composer object were created like following:

this.composer = new THREE.EffectComposer(this.renderer3D);

So as for the renderer, the composer needed to have the size updated after the event handler function like following:

if(instance.renderer3D)
    instance.renderer3D.setSize(instance.dom.clientWidth, instance.dom.clientHeight);
if(instance.composer)
    instance.composer.setSize(instance.dom.clientWidth, instance.dom.clientHeight);

And this fixed the issue perfectly :)