It's far from clear that draw-on-top paywalls qualify for the protection offered by either the DMCA or the CFAA. Even if they did, the mechanisms by which this

It's far from clear that draw-on-top paywalls qualify for the protection offered by either the DMCA or the CFAA. Even if they did, the mechanisms by which this specific extension works are indistinguishable actions users take for many other reasons. The legal notice is a gamble that the extension author doesn't want to spend the money to find out the hard way.