From the XChangeProperty man page:
"If the specified format is 32, the property data must be a long array."

This reverts commit b6a1cff6.

1) winwidget.c winwidget.h New function winwidget_update_caption using code in winwindget_render_image. This code was removed from the latter, and replaced with a call to winwidget_update_caption.

2) Image caption is updated after running action when in slideshow mode.
3) Running action in slideshow mode no longer changes the image automatically.

Does not yet work with initial zoom value != 100%