alt Hacker NewsWhen you point your browser at a website the browser creates a (transformed) local copy of the information that is owned by the website itself. The browser needs to do that to render the website on your screen. Is it a violation of copyright (that the website is willing to tolerate because it profits from advertisements)?
No, because your browser is dealing with the distribution of data in a way intended by the copyright holder. You also aren't redistributing the webpage after rendering. Client side modifications fall under fair use which is what keeps the likes of ad blockers and other page modifiers legal.
What would violate copyright is if you took that rendered page, turned it into a jpeg, and then hosted that jpeg from your own servers. That's the copying that would run afowl of copyright law.