Creating Animation with selected Scenes

Having recently upgraded to Pro 2021, I find that I can’t do something I used to be able to do very easily with my older version and hoping someone can show me how to do it now.
It’s simply to create an Animation of my model using just some of the saved scenes and not all.
This used to be very easily done with a dialog box in the Scene Manager but there seems to be no mention of it now and I can’t find anything about it in the help pages.
Can anyone guide me please.
Thanks Jonathan

In the Scenes dialog is a checkbox.

Thank you very much.
I realised soon after I’d posted this that it was hidden at the bottom below the edge of the frame.
I’m not a big fan of the side panel - I find myself constantly resizing panels and scrolling up and down.