Thank you for reporting the issue. Our investigation revealed that the problem manifests in multiple use cases.
We have fixed the issue in some of the use cases and are currently working on the remaining ones.
Please update your InDesign to the latest version, id 14.0.3 to try out the fix.
We shall update here once we have addressed all the remaining use case
We appreciate your cooperation.
-InDesign TeamAlexandra Bourdelon commented
Yes I am having the same problem if I highlight text or click in text box all of a sudden text disappears although still there as can highlight and if change colour and change back to black in reappears but then happens 5 minutes later again. anyone know how to fix?