Window locking issue

I am using a macbookpro, OS12.5, Illustrator 27.9

I have all my workspace windows (artboards, lyers, properties, etc) stacked vertically on the right side of the main project window. When I origanlly set up my custom workspace, as I dragged a new workspace window near one already in place, a blue line appeared and the two windows docked together vertically. However, when I dragged this whole collection of workspace windows close to the main project window, a blue line did not appear. They clicked together but are apparently not locked that way because every time I re-start AI, those workspace windows appear over on the left side of the monitor, not docked to anything, and I need to drag them back over to the right side. Is there a way to dock (lock) workspace windows to a main project window on the right or left side?