This is an odd situation.
On Dec 19, 2013 this comment was made in lib/tasks/assets.rake:
# in the past we applied a patch that removed asset postfixes, but it is terrible practice # leaving very complicated build issues
It turns out my plugin relies on non-digested images since they are used in my templates as src’s.
Why am I only asking this now? Because I think on my production box there were old copies of non-digested assets lying around from pre-Dec 19. I only just now deleted them for an unrelated reason, and the problem suddenly emerged.
What should I do? Avoid using img src? Is there some way to get handlebars to add the digest? Should I use all background-image? It appears that my plugin asset paths are not digested in the compiled CSS file either.