The developer (Cameron Kaiser) mentioned it in an article a few months ago. As I remember, Classilla is not dead and there are some simple updates that he'd like to do at some point. Classilla is a lower priority for him than TenFourFox.
Is there a way to make donations towards the Classilla/TenFourFox projects? Looking at TFF's mobile site I was unable to see anything. I use both fairly regularly, for the past several years, and wouldn't mind giving a little back.