There are limitations in using the embodied PDF Reader: no search, no text selection, etc.
Why not using a well established and very lite Reader as SumatraPDF. Here a way in which several programs use a full integrated version of it: http://www.ghisler.ch/board/viewtopic.php?t=27145
It is able to read epub, djvu, among other things!
Thanks for the recommendation. We’ll be looking at our options for improving the PDF abilities for 2.0 and what alternatives are out there that we might be able to support. I know a lot of folks use Sumatra, but I’ve only seen it myself as a standalone application; I appreciate your link!
Here a program that, after suggesting the link above, was able to offer an option to implement it quite nicely. Contrary to the browser’s pdf plugins, there is no waiting time in reading pdfs with this solution. Link: http://www.rttsoftware.com/pdfe.html. There is a trial to test it yourself.
A new PDF option or the original would be cool. (It used to work from the first beta until the pre-release, but when they switched to QuickPDF, it didn’t. Boo. 
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