Sensor Tower (https://sensortower.com/) makes a lot of popular extensions, like StayFocusd https://www.stayfocusd.com/. They seem to resell ad data (in violation of [1]?) and ship likely obfuscated code [2] (in violation of [3]?), but there's no enforcement or even clear reporting mechanism.
[1] https://developer.chrome.com/docs/webstore/program-policies/...
[2] https://robwu.nl/crxviewer/?crx=https%3A%2F%2Fclients2.googl...
[3] https://developer.chrome.com/docs/webstore/program-policies/...