I absolutely love CustomReader* and wanted to post a quick note of appreciation for all of the hard work, as well as a few words of encouragement for any possible updates (but no pressure!).
FWIW I'd also be happy to purchase a working extension for a couple of bucks, if that's any incentive. :)
Cheers and thanks again!
* P.S. I stylized CustomReader after Metafilter, with white text on a venice blue background #005B8E, dark blue side panels #004970, and gold links #C5C502. Nice and easy on the eyes. [Custom Reader works on all but the side panels, which you can turn black with El Capitan's very limited custom settings. Better than white, but still not as elegant as CustomReader :)