Bookmarklets
Bookmarklets are bookmarks that contain JavaScript instead of a URL. You can execute them while reading a webpage, and they typically do some quick analysis and display their results.
Installation
Bookmarklets can be installed by dragging the specified link to your bookmarks toolbar. If you are not able to drag and drop, copy the link location, create a bookmark manually, and paste the copied code as URL.
We suggest you add all suggested bookmarklets to each and every browser you have (you never know when you need them).