Sponge texture becomes weird (an icon set?) when animation of mopping ends

This was going on on the last few live branch patches as well. When mopping, the sponge turns into what looks like a set of different-colored things in a mostly-transparent texture; this happens apparently the frame after the animation finishes, as pausing makes the dupe return to the standing animation instantly, and it doesn't show up between mop actions, just when a dupe is starting to do another animation.

lshw_output.txt