Alt+F4 closes only current project; not all open projects

Running Scrivener for Windows ver on Windows 10 (latest build).
Normally, I won’t have more than one project open in Scrivener, but occasionally, I will keep another project open for convenience.
I will go to File > Recent Projects, and tick off the projects I want to have open.
When I want to end a session and close Scrivener, I would hit Alt+F4 (the shortcut listed for Exit), but doing so closes only the current project, and not any others I might have open at the same time.
If I hit Alt+F4 again, the new current project will be closed, and Scrivener will be closed if there are no more projects open.
Unfortunately, next time I start Scrivener, only the last project that was open (before hitting Alt+F4) will re-open.

However; if I click File > Exit, then all projects will close at once, and when I re-start Scrivener, all projects I had open during my last session will re-open, with the project I was last working on appearing on top.
If I hover my mouse cursor over the Scrivener icon in the taskbar, I see all of the projects I have open at the time, and can select the one I want to work on, leaving the other one open.

What confuses me is that next to File > Exit is the shortcut Alt+F4. So why doesn’t Alt+F4 perform the same function that File > Exit performs?
Is there a setting hidden deep within options that I have failed to tick or have ticked by mistake?

Thanks for your help

Hi. I think the base function of Alt-F4 is to close the current window; if that window happens to be the only window currently being generated by the program (IOW, the only “project” currently opened by Scrivener), then closing that window will also terminate the program. From that pov, what you are describing is essentially correct behavior, but for one wrinkle…

The File > Exit text that shows Alt+F4 as its shortcut key is misleading and self-contradictory: pressing the Alt+F4 shortcut key does not “exit” the program and will only close the current window/project; but opening the File menu and pressing the mnemonic ‘x’ will shut down Scrivener completely. At least that’s how it’s working here with Windows 10 and Scrivener 3.

A number of Scrivener’s menu commands produce different results than their supposedly corresponding key commands.

Seems someone mixed up Ctrl-F4 and Alt-F4. The former should close the current document, the latter the whole application. Same as ⌘W vs ⌘Q on macOS.

Ctrl+F4 and Alt+F4 do exactly the same thing for me.