This add-on collects NO DATA at all. The extension, by and large, is a local copy of the DjVu.js Viewer which is available on https://djvu.js.org/. It allows you to open links to .djvu files right in the browser (via context menu) and .djvu files from a local drive (after you open a page with the viewer you can choose a file). Also, in case of an indirect (multi-file) djvu document you can bundle it into one file via the extension. Furthermore, it processes <embed> and <object> tags with .djvu files and replaces them with the viewer. So the extension may be, in a sense, a substitution of the Cuminas' native DjVu plug-in. Since all operations are performed on your machine, the extension can work without an Internet connection. All source code is available on https://github.com/RussCoder/djvujs The extension is based on DjVu.js - the library which allows to process djvu files right in the browser. The library is still being developed, so there may be some bugs. If you have a djvu file which is incorrectly opened with the extension, I will appreciate a lot, if you send the problem file to me at djvujs@yandex.ru - if you do it, I will be able to fix bugs and improve the library, which is an open source project.