Avoid new windows to start out maximized?

With Ubuntu 24.04 und Unity, it seems that many windows, when newly created, will start out maximized instead of their normal default size which I see under all other desktop managers. This happens e.g. with new Firefox windows and with new default terminal windows. How can I configure things so that the proper non-maximized default size is used when the window is created?
What is also annoying is that when I then click the de-maximize button in the title bar of my new Firefox window, it gets restored to an absurdly small size ! When I correct the size and create yet another new window, the same happens, it does not remember my preferred window size at all!

This is something that just works right and without forcing window sizes on me in all other desktop managers I have tried: they always start those windows non-maximized and with the size I last chose.

See my comment in your other post:

Is this Ubuntu 24.04 with Unity installed as an additional desktop package or Ubuntu Unity?

At the bottom of this page there are options to contact the maintainers:
https://ubuntuunity.org/

Thanks.

Sorry, I have probably used the wrong name then … I am using the window/desktop manager that is just called “Ubuntu” in the options menu before logging in.
So is “Ubuntu” also the official name of the default window/desktop manager now?
I could not find any name of version information in the “Settings” - “About” window, this only tells me about the OS, not about the window manager / desktop system.
In the system details it also says GNOME version 46 and Windowing System “Wayland”