Strictly a beta Rated 3 out of 5 stars
The beta nature of pdf.js is quite evident, and makes it unusable in many cases. Text rendering is highly faulty, and often characters that are composed of lines, such as "=", are not rendered at all. It also lacks a search function, as Firefox's search will produce misleading results with the non-rendered pages. Displaying pages is extremely slow and jerky, requiring seconds just to scroll down to new pages. Finally, the huge memory consumption fills up 4GB with just a few pdfs, which is probably due to the in-browser nature of the plugin.This review is for a previous version of the add-on (0.3.175).