Black bars on left and right edges of screen

[zuffdaddy]

When playing King's Bounty in 1280 x 720, I get two black bars on both the left and right of the screen, as if it's not scanning correctly in widescreen.

Numbers, such as unit life and quantity of my armies render in these black bars, but not the artwork of the game.

Is 1280x720 not supported natively in this game?

Thanks in advance, and I love this game btw, I just wish I could play it on my monitor's native resolution!

Screenshots (Notice how in the second screenshot you can see numbers in the dark void of the black bars!):

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