I am in Revit 20 for reference. Have not noticed the issue happening in other versions.
I opened a large Revit job and opened a live view, upon doing so all the section references disappeared.
I checked the command history and this is what I saw:
When I click on the "Undo 1 Command" they return, but once I go back to the file, they disappear again. I have ran all updates available on version 20 of Revit as well.
Trying to find a solution without having to uninstall/reinstall. If anyone has any advice, it would be greatly appreciated!