Tiller Foundation Sheet Row 1 headings

Suddenly, all the Row 1 column headings of my Tiller Foundation Sheet have vanished and been replaced by single down-pointing arrowheads. The sheet is otherwise intact and receiving downloaded transactions. Did I inadvertently do something to cause this phenomenon? Can I just re-enter the headers safely? Do the little down arrows mean anything particular? Ron

Posting a screen capture of that part of your sheet would help determine what’s going on, but one possibility is that you have filters turned on. See if ‘Remove Filter’ exists in the Data menu, and if so, choose it and see if that fixes it.

Yesterday Nov 3 I witnessed a phenomenon that sounds like it could be similar. I was working in another sheet and the first header row of my data table (not row 1, not even column 1) suddenly turned green with triangle down arrows (different from filter icons). It happened for no conceivable reason without warning. A lot of other formatting was also temporarily lost. It was a bit alarming and definitely nothing I enacted. I wish I had taken a screenshot but I did not. However, the issue was resolved after reloading the sheet and everything returned to the expected condition. I chalked it up to a Google Sheets glitch. I had never seen that behavior before, even with daily sheets use over years.