Thank you for your support. The issue is now fixed in the latest update of InDesign.
Please upgrade to the new InDesign 14.0 from your Creative Cloud Application.
If you are unable to see the update yet, click on the menu (three dots) on the top right corner of Creative cloud app and click on “Check for App Updates”.
Let us know your feedback in the comment section.
InDesign TeamAnonymous commented
I also could not expand my pallets in InDesign either. Tried the detach floating pallets from upper right of page layout and that Did work. I can now expand the pallets.
Am I going to have to do this EVERY time I open a document now? Why am I paying $57. a month for this kind of nuisance? Get with it Adobe and fix this monopoly you're running!