How to subscribe?
At the top right corner of the new tab page, there is a "Free plan" button or a notification about limits "Free plan limits reached". Click on it and use the Upgrade button to upgrade to the Pro plan.
You can also get a Pro plan for free by inviting your friends to sign up.
What plan do users get after signing up?
All users get a Free plan by default.
Can I try Pro plan features before subscription?
During a ~1 month period, all new users have no limits and access Pro plan features (split view, workspaces, multiple accounts, etc.).
Starting from week #3, users periodically get a reminder about the Pro plan if they use paid features.