• read this first: https://www.webkit.org/blog/3476/content-blockers-first-look/
• start by adding a new extension target to your iOS app of type “content blocker”
• launch the app using the main target’s scheme + a call to SFContentBlockerManager.reloadContentBlockerWithIdentifier() with the extension’s id in application:didFinishLaunchingWithOptions: to auto-reload the blocker in development mode
• if you don’t call reloadContentBlockerWithIdentifier() then you need to switch the blocker off and on again in the Safari settings (stop the app in Xcode if the switch is not moving)
• use inspector from desktop Safari to inspect the Safari in the simulator in order to find specific things to block
• things like periods in the url-filter regexp need to be escaped with double backslashes, e.g. facebook\\.net
• if you use if-domain, it needs to be an array, even for one element
• domain foo.com might not match www.foo.com even though I think it’s supposed to (UPDATE: They've changed it in one of