Hello.

Bookmarklets are an unsung superpower of Desktop Web Browsers. They are not as powerful as Chrome Extensions, they require a user gesture, they don't have access to browser specific API's (such as chrome.*), yet I love them. In their simplest form (a Bookmark) they navigate you to a URL; more complex forms (Bookmarklets) navigate to a javascript: URL which means you can run simple automated actions that run in the context of the page, creating functionality that the original developer didn't get around to creating just yet, just at the click of a button.