A screenshot of MacOS computer windows running in virtualization stacked on top of one another starting with minivmac running System 7.5.5, SheepShaver running Mac OS 9.0, Virtualbox running Rhapsody DR1, Mac OS X Server 10.4.7, Mac OS X 10.5.8, and OS X 10.10.5. All have the about windows open showing the versions.
https://files.mastodon.social/media_attachments/files/111/970/093/582/610/634/original/39246f1b58a7c48c.jpg