Also there is something wrong with full screen mode that makes the game run slow. Which is particularly stupid because if you set the game to windowed mode with a window size equal to the resolution of your monitor it looks the same as full screen but plays faster.
This game has a problem with graphics in general. If I use full screen mode on my system I'm unable to get back to windows via the quit function. All I get is a permanent black screen, unability to get the task manager, and all I can do is a hard reboot. So I play with windowed mode and it's fine. That's another strange thing you report from the game's behavior. Also I didn't know the map mode thing.
On my end I sometimes click on a system from the galaxy view, do my thing, switch back up to the galaxy view, aaaaaand it's slow. Save/quit/reload and it's gone. Usually that was the time when I would get the giant model on galaxy view bug, when it was still a thing. It is more frequent and prominent if using a heavy galaxy texture mod.
I suspect this game is haunted by reminiscent ghosts from being traumatized in its childhood by a mean GPU.
