I don't recall someone talking about this but on my system the windows expand/collapse appears to have a number of problems.
1) In unexpanded state, windows shows "expand" icon at top right, as all programs do.
2) But when the window is expanded to full screen, this icon disappears (unlike other programs). Instead, the "minimize" icon shows up as part of a toolbar that can be moved around. Maybe this is intentional. I don't have a problem with it other than it makes the process different from all other programs, which you have to remember.
3) The problem is that when the window is maximized, the title bar at the top also disappears, and the icon in the windows taskbar goes blank. If you're working on several files, it makes it difficult to figure out what's what.
Normal title bar in unexpanded window: