We present a new web automation system that allows users to create a smart bookmark, consisting of a starting URL plus a script of commands that returns to a particular web page or state of a web application. A smart bookmark can be requested for any page, and the necessary commands are automatically extracted from the user's interaction history. Unlike other web macro recorders, which require the user to start recording before navigating to the desired page, smart bookmarks are generated retroactively, after the user has already reached a page, and the starting point of the macro is found automatically. Smart bookmarks have a rich graphical visualization that combines textual commands, web page screenshots, and animations to explain what the bookmark does. A bookmark's script consists of keyword commands, interpreted without strict reliance on syntax, allowing bookmarks to be easily edited and shared.