We have an installation of SharePoint 2013 Enterprise, I am accessing with an Exterprise CAL.
I have noticed that seemingly randomly, the part of the list view page that shows "new task" (or "new item"), the list of views etc. disappears. It can happen with any type of list as far as I know. It can reverse itself (these features"come back") with no warning. I think but am not 100% certain that it only happens after I edit a view. When its correct the text "new task or edit this list " appears.
Another funny thing is that whenever the page is wrong (the features are missing, i.e. "new task or edit this list"), a new widget for "Add a new item" with a plus sign appears on the list view page, at the bottom of the list items, but that is never there for a page that's working correctly.
Any ideas? Its EXTREMELY annoying.