The fix for this issue is now available in the latest update of InDesign – version 16.1
Please update to this version to get the fix. To prevent problem on existing documents and see the footnotes again, you will have to force recompose the stories.
To force recompose stories, you can use the shortcut Command-Option-/ (slash) on Mac or Ctrl-Alt-slash on Windows
An error occurred while saving the commentYolande Martel commented
Same problem. I could track with Time Machine that it was Ok when I worked on the specific article, but at the end there were 4 articles of a journal with some footnotes text missing. I opened the document by idml and footnotes reappeared. But this a major bug. - Yolande Martel