To keep things simple, upgrade here.

In addition to previous versions benefits, Pushwoosh Web SDK 3.0 provides you with:
Better push adoption rate
Collecting information about opted-out users became much easier than it ever was. Optimise your push campaigns segmenting and evaluating the entire userbase of your website.
Behaviour based push subscription
Define the exact moment for asking a user to opt-in. You can also demonstrate a custom banner.
User reaction feedback
Precisely track user activity via additional events and reach a new level in understanding how customers react to your push campaigns.
Push by User ID support
Send push notifications to the last device used by a customer so that there’s a higher chance to reach them.

We’re constantly gathering feedback from our customers and already working on the next update. Be ready for Rich Chrome notifications, web push notifications display time adjustment and many more tremendous things.

In addition, we continue to support the previous version for the next 6 months.

Once again, here’s the link to the guide.