in Spectacle, version Version 16.04.3 - So Much For Subtlety, the enter key on the keypad does nothing after selecting a rectangular region. A user must use the main enter key in order to save the screenshot. Please add support for both enter keys.
Works for me with Spectacle Version 16.12.3, both Enter keys behave in the same way
https://git.reviewboard.kde.org/r/128054/