https://wiert.me/2020/12/03/im-using-delphi-xe-10-2-empty-documentation-tab-means-you-need-to-update-to-either-the-documentation-hotfix-or-10-2-3/
I'm using Delphi XE 10.2: empty documentation tab means you need to update to either the documentation Hotfix or 10.2.3