Dynamics 365 solution error - Components are missing, import the managed solution with these Components (Active)!

I was importing my unmanaged solution then the error has occurred.

I was using a new UI. After spending some unpleasant time researching and trying different things I came across this post in the Hosk’s blog:

https://crmbusiness.wordpress.com/2020/06/02/dynamics-365-solution-error%e2%80%8a-%e2%80%8acomponents-are-missing-import-the-managed-solution-with-these-components-active/

Thank you very much, Hosk, you are truly marvelous!

I realized that I have to switch to the Classic interface to get a meaningful error.

I did. I tried to import the solution using the Classic interface. I was missing one view in my solution. It took me 5 minutes to fix them re-import.