[RESOLVED] Strange operation when opening via .vpb

Up until a few weeks ago if I open a .vbp file, just study the code and make no changes, I could close the IDE with no prompt about saving. Indeed, if no changes were made, why would I need a save prompt.

Lately, I have been getting the prompt. Can anyone hazard a guess as to why this happening?
Is this the preferred behavior? Is there an option to save only when I make a change.

Thanks