Since I installed the Gutenberg editor, the “Featured Image” button had vanished. So I did the following:
1. Deactivated all plugins and the button was back.
2. Reactivated each plugin one by one and checked to see if the button was still there after each activation.
3. As soon as I activated the “Inbound Pro” plugin, the featured image button vanished again. (Screenshot attached)
So, it is probably a conflict between Inbound Pro and Gutenberg? Please advise.