The fix for this issue is now available in the latest update 14.0.2 of InDesign 2019.
If you are unable to see the update notification yet, open the menu (three dots) from the top-right of Creative Cloud desktop application and click on ‘Check For App Updates’.
Once the update button is shown against InDesign, click on the button to update to Id 14.0.2.
If you face any problems with the new update, do let us know in the comments.
Thank you for reporting the issue. It is under review now.
Please update InDesign to the latest version, InDesign CC 2018 (13.0) for the fix of the issue.Glen Bal commented
Great! This fixed the problem!Glen Bal commented
The headerrows get invisible or with a height of zero when you open an idml-file.
To recreate this issue:
1. Open Indesign and create a new file.
2. Create a table with a headerrow and save the file it as idml.
3. Open the idml-file in Indesign
What do I expect? A roundtrip to idml should give me headerrows.
Version: Indesign CC 2017.1 (126.96.36.199 x64 Build) on Windows 10
Attached is an image of the table when it is saved and an image after opening the idml. Also attached you can find the idml-file.