I noticed that using the Single Property View widget to change the value of a property on the widget itself (by setting the Object target as Self in the widget constructor) marks the current persistent world as dirty, since the widget’s outer is the current world.
This is a pretty big problem since a lot of people on my project work in the same persistent on different sublevels and they get prompted to save the moment they click any Single Property widgets, when in fact they do not need or want to Save/Check Out the persistent level since they have not actually changed anything.