Signals Notebook: Can't find deleted attachment in Trashed items

I deleted a ppt file form Signals; when I wanted to restore it from trashed items I could not find it.

Actually there are very few items in the "trashed items" list i.e. the list is by far not complete.

Also, are you going to remove the “trashed items” option in the user menu? 

Solution: 

You can't "untrash" content files from the Trashed folder anymore, instead you can revert them from the History. 

You can learn more about History from User Guide -> Working with Resources Menu Icons -> History