If you've been meaning to try the pro tier of Google's streaming games platform, then you have some quick work to do to try it for free. Lenovo is offering anyone three months of Stadia Pro for free, if you sign up to its Legion Gaming community. You'll also have to jump through a few other hoops, but we've confirmed that it's working for new users in the US, at the very least.
First, head to this promotional Lenovo page. Go through the "Click here to enter" portal. You'll then need to sign up for a free Lenovo Legion account (you can use Steam to log in among others), then link it with the Legion social accounts on both Twitch and Discord. Once you've made all three of those connections, you can click the "claim" button to sign up for Stadia Pro.
You'll still need to enter credit card information for a Pro account, but it won't actually charge you until after the three month trial ends. Until then, you can claim free games with Stadia Pro, and play them at up to 4K quality on Chrome (desktop browser or Chrome OS device), Android, the Chromecast Ultra, and even an iOS gadget. This is the same freebie that you'll get if you buy a new Lenovo gaming PC, but for now there's no external purchase necessary.
The promo deal apparently does not work if you've been a Stadia Pro subscriber before (we tried), and it can't be redeemed with Google Workspace accounts (ditto). We're also not sure if it's valid outside of the United States, though these promotions often are. Lenovo presumably has a limited amount of free trials to give away, so get on it quickly if you'd like to participate.