When I plug an external media e.g. a usb stick, choose "Open with Files" from the pop-up message, nautilus opens the mounted media. If I click on the eject button on the sidepane, I get no error messages. But if I first navigate to a different directory, and then click on the eject button I get the following message (which doesn't affect the eject operation):

"This location could not be displayed.

<volume_name> could not be found. Perhaps it has recently been deleted."

It's trying to navigate to the unmounted media. Although harmless, I don't think the user should get this message.

I've attached a short screencast.