This is the Build ID: 6.0.2.1-2.fc28 that comes with Fedora. I am seeing cell A1 randomly disappear when I reopen a large spreadsheet. This started occurring when I upgraded from Fedora 26 - libreoffice-5.3.2.1-2.fc26 (I think). I share this spreadsheet with another computer and open it in 5.3-something there and don’t see this happening.
Anyone else seeing this kind of random thing?