This was a nasty bug that I discovered when working on a project at work
probably over a year ago. I had worked around it, but ease.js was largely
stalled at the time; with it revitalized by GNU, it's finally getting fixed.
See test case comments for more information.
This is something that I've been aware of for quite some time, but never got
around to fixing; ease.js had stalled until it was revitalized by becoming a
GNU project.