Bookmarklets are tiny pieces of javascript code stored as a bookmark with javascript: URL
scheme. They're often used to extend functionality of a third-party website.
Urls in the parentheses indicate which website the bookmarklet is intended to work on.
- ytsavetime.js (https://youtube.com) -- saves current play time in localstorage.
- FuckRBooks.js (https://e-library.ufa-rb.ru/) -- bookmarklet that allows to print the book. Uses a large amount of RAM.
- libDL.js (https://e.lanbook.com) -- allows to download PDF from the site.