Was working in page with two column layout.
I attempted to copy/Paste a section and the mouse cursor disappeared.
I then attempted to Preview and return to Edit to get mouse cursor back--but to no avail.
I then decided to save so that I could edit later only to find that all the contents for the whole right column was gone. This was the detailed section and I spent quite a bit of time collecting and getting the right Jira issues details in.

Support zip file is attached