There's an "Update" entity in the sidebar of all my Finder windows:
Note that there is no eject button on this entity.
Get Info (⌘I) on that entity reveals that it is a 245 GB APFS drive:
<...>
What is it? Whose is it? Should I do something about it?
--Gil
MacBook Air 13″
I saw that earlier and, at the time, I didn't realize that "drag it out of your sidebar" was a bona fide operation. I tried again and -- perhaps dragging the icon a bit farther out -- it worked. "Update" no longer shows in any Finder sidebars.
Thanks, Randall.
--Gil
This reference will answer your question:
What is Update under Locations in Finder? - Apple Community
What is "Update" under Locations in the sidebar for Finder windows in Sequoia 15.6.1?
