I believe that clicking the ⋯ icon:

is meant to bring up the menu that contains the "revert to this revision" option, but clicking it does nothing for me on Endless OS (Linux, GNOME 43, Wayland) with alpha20.

It worked for @jgbourque with alpha20 on Windows. I can test on other linuces to see if it's an Endless OS-specific problem, or if it occurs on newer GNOMEs as well.