While going back from the options menu using the p button (escape button), the complete pause menu system disappears, and the key event in the options menu widget is called every time one presses the p button afterward. I’m using the following for the back button inside the options widget:
Since you Remove / Add to the viewport / parent, the Construct Event will fire.
Do note that that EI comes with priority settings and its own input consumption options. Might be an overkill in this very scenario but could be useful in more complex ones.