How do I activate Blend4Web?

I’m very interested to try out the force normal tool that this gif show https://www.blend4web.com/doc/en/_images/vnt_img12.gif but I cant find it. I dont have it in my tabs like everyone seems to have in the turtorials, and no one shows how to put it there.

You need to install the Blend4Web addon
http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Import-Export/Blend4Web

Thanks Richard!