Pihole blocks ads for an entire network, so why does a content blocker have to be built into the browser? Can't it just be a separate app you run, outside the browser? Even if the browser is using HTTPS the URL and IP address for everything not from the site you are on is visible. The app could even run as a fake proxy. Scripts would be harder to block if they are sent encrypted, but since you can view the scripts in a browser and hence know the exact content of the script maybe it would be easy to snip them out of the encrypted stream by automatically generating signatures or formulas for what to snip for the scripts from various sites. You could even use an embedded browser in the app to decode and format the entire page, automatically determine what to snip, do the snip, and then forward the modified stream to the users primary web browser (with some delay). Any checksums could be modified appropriately. The app could present a GUI in the primary browser that the user could use to decide what to block. Are the page contents protected by a cryptographic signature? Does not seem like it would matter since the embedded browser certainly has the ability to decrypt everything. Data in the reverse direction could be sent unmodified. Maybe the slowdown caused by filtering everything this way would be unacceptable to users? Some users might find it acceptable in exchange for greater control.