SDL_WINDOW_BORDERLESS inconsistency

I’m using the SDL_WINDOW_BORDERLESS flag to remove the title bar, but it’s giving inconsistent results on different PCs (SDL 2.0.11 if it matters). Both are Dell laptops, both are running Windows 10, but on one there’s a thick black border on two sides of the window (with the content shifted) and on the other it’s working as expected:

PC 1:
borderless_bad
PC 2:
borderless_good

The machines give identical results if I remove the flag. Any possible workarounds?