I saw this when I logged out from my account. Says no Activation required. See attached for screenshot.
*Offer valid now through 12/31/2020. Earn a $10 statement credit on your Discover credit card account when you make a purchase of $50 or more using your Discover card at PayPal and redeem any amount of Discover rewards at checkout. No Activation required. PayPal qualifying purchases are those made through the PayPal wallet online. Payments made when you send money to Friends and Family via PayPal using your Discover Card, point-of-sale transactions using PayPal Here, or through the Xoom transfer service are not eligible. Purchases made using tap-and-pay, mobile or wireless card readers, virtual wallets or similar technology will not be eligible. Offer is not transferrable and limited to one offer per account. Statement credit will be posted to your account within two billing periods after the end of the promotion. For complete details on how to Pay with Rewards with PayPal see PayPal.com/Discover. Pay with Rewards will be available for eligible credit cards on eligible purchases. All reward redemptions are subject to Discover's reward program terms.