> More likely, advertisers will need you to insert a “bootloader” that fetches their code and passes it to eval().
Sounds like legal precedent waiting to be set. “Run our code so that it looks like your code, acts like your code, and has all the same access as your code” seems like it should be a slam dunk if said code ends up doing a Very Bad Thing to your visitors.
But of course that’s assuming common sense, and the law’s relationship with that isn’t always particularly apparent.
There is already plenty of precedent for real-time-served ads which are annoying, or malicious, or install malware; or outright exploit vulnerabilities in the browser.