Technically, Increase is correct. Although keystates are updated with a 'Sync()' call, most keys do not reset correctly for state checks after app interruption. For examples, 9 (tab), 13 (enter), as well as 27 (escape) will all fail to reset for state checking after a message box or other interruption. So even after the app/game is restored, the state check still shows '1'
until the same key is redundantly pressed and released a second time.
An exception to this is the alt key. Both indexes 18 and 262 will reset to 0 after app interruption.
So it is, in a general sense, a bug. I'd recommend reporting it on the GitHub list.