Someone asked on ExtensionPay's discussions how to charge on their own landing page before anyone installs. Setups that track paying users from inside the extension want the extension first. With license keys you can flip the order, because the key is the proof of purchase and it can arrive before the extension does. We make Keyturn Kit, a starter that works this way, so take this with that in mind.

The order of things

Buy button on your page, linking to a checkout (Lemon Squeezy here; Polar, Dodo Payments, Gumroad and Payhip work the same way).

The confirmation screen and the receipt email both point to your Chrome Web Store listing. The receipt carries the license key.

The buyer installs, and the extension opens a page that asks for the key.

The extension activates the key with the provider's license API.…