The fix for this is now publicly available in the latest InDesign update, 15.1.1
Please update to the latest version to get the fix.
Adobe InDesign team
An error occurred while saving the commentAnonymous commented
appalling! had the same issues and now took advice to roll back so I can now produce the PDF for my client's document who needed it 2 days ago! Pay a lot for this program so I'd like to know when all this is fixed.