Actions: "Replace existing terms" checkbox is not persistant

When I make a new advanced action available, to "modify node's taxonomy terms" at admin/settings/actions, I am able to successfully create an action to replace one term with another. I call it something like this:
Taxonomy Term -> TERMNAME (Replace)

However, each time I go to edit one of the term actions, the "replace existing terms" checkbox is blank. (Image attached)

The action actually does successfully replace terms in bulk views operations, but it's disconcerting that the action configuration form does not show the replacement as checked, after first creating it.