I opened a .rtf file in LibreOffice, and there are a bunch of strange, bold zeros that I cannot delete and which were not present when I viewed the same file in Microsoft Word and in TextEdit (I am using a Mac). Sometimes, when I frantically clicked around trying to highlight them or manipulate them in any way, they would show a gray background behind them, but I still could not select them or delete them. They seemed to coincide with blank lines that had been created by pressing the return key repeatedly, but this is not constant throughout the document.
Upon closing and reopening the same document, all of the areas where there were zeros sometimes shows a numbered list that also cannot be deleted.
Has anyone heard of this before? How can I get rid of these zeros/lists that cannot be deleted? And what does the gray background mean?