This is something that's missing in the 4th game.
The case is a standard version of the 4th game, not the Equilibrium version.
It's extremely inconvenient to play in non-full-screen mode – there are glitches when viewing the map, and when trying to move it (clicking on the mini-map and dragging the mouse). There's also a problem with dragging the map if you try to move the corner of the global map with the mouse to scroll. It's extremely inconvenient for viewing.
In Heroes 3 and 5, there's the option to play in non-full-screen mode, which is very convenient. I would like that to be available here as well.
Good afternoon! Try pressing F4, it will switch to windowed mode, and you'll see an options panel there, and you can experiment with it. I was very comfortable playing at 1920x1080, the only thing was that there were occasional crashes to the desktop during battles...