Virtual desktop shrinks itself when game launches

[P.P.A.]

I wish to run games in a window, and thus used the emulate virtual desktop option, setting the resolution to 1280x1024. During the brief moment when the virtual desktop is loaded before the game, the window has the correct resolution, but as soon as the game launches, the window shrinks itself down to 800x600. This happens with different games (Anno 1503 and OutRun 2006)—which natively support resolutions higher than 800x600 (Anno 1503 has 1280x1024 enabled in the in-game settings)—and whether I use PlayOnLinux or Lutris to set up Wine.
I am using Xubuntu 20.04.

[spoon0042]

Does changing the resolution in game restore it to 1280x1024? afaik that behavior is intentional.

[P.P.A.]

Does changing the resolution in game restore it to 1280x1024? afaik that behavior is intentional.

I thought this didn't work because I had switched back and forth between resolutions in Anno 1503's menu a few times already, re-launching the game in between—but it turns out that the in-game menu is always locked at 800x600, while actually starting a game session then applies the selected resolution—and scales up the Wine virtual desktop accordingly!
The same was true for the other game, once I'd edited the .ini file.
Everything works as it should now. Thank you.