I am running emacs under (Ubuntu under) WSL 2 and I can bring up the first frame maximized (i.e. almost full screen, leaving the Windows "task bar" exposed, the -mm option does that). I would like to bring up other frames the same way, so that by switching tasks on the task bar, I see only one Emacs frame. I can do this by creating a window and clicking on the maximize button, but I would like to do it within Emacs (using make-frame) because I layout the emacs windows/buffers based upon the frame real estate and doing it as two steps gets the internal windows slightly the wrong size.
In the old X days, I could do it with geometry frame-parameters, but WSL 2 doesn't seem to respect the top and left parameters and makes a frame where the maximize button is outside the display area so I cannot even click on it without first moving the window and then clicking. Moreover, I'm not certain that the geometry I am specifying is exactly the right size, which may be exacerbating the problem.