Slow, lacks two-finger zoom and is unable to print math Rated 1 out of 5 stars

Previously I said this:
The good thing about this addon is that it works (I have not done extensive testing, but my previous addon started to crash on me with the latest update of Firefox).
The bad thing is that the rendering is pretty slow (e.g., compared to using Chrome for the same purpose) and also that it lacks the familiar two-finger zooming.
Now, after some testing, I have to refine my claim. It works -- until you try to print math, which, most of the time comes out as gibberish. So the addon is simply unable to handle special fonts/characters. Horrible. I am considering to stop using firefox because currently no addon for viewing pdf documents fits my simple purposes (which includes correct printing). At least they should not have disabled the option of using other addons.
Some reviewer above said that Firefox 19 makes all addons obsolete as it includes a built-in pdf viewer. Big secret: The built-in pdf viewer seems to be just this addon. And it is still unable to print math. Why do Mozilla people need to make silly decisions like this? Why change something that worked? I was using fx-quartz-pdf-1.2.0 happily -- I just had to change inside the xpi file the version number accepted until the previous upgrade to Firefox when they arbitrarily decided that from now on all users should use their useless addon.
Why!? Why!?!?!!?!? Why!!

This review is for a previous version of the add-on (