Hello everyone!
I am unable to add a missing thumbnail, as shown in the attached screen capture, in Linux (Ubuntu) file manager. As you can see, the book "Cheryl Strayed - Wild" doesn't have a thumbnail.
I am trying to add it with Calibre E-book editor with dropdown menu (Tools --> Add cover). But I am not sure if that is the right way to accomplish it.
Does anyone have the magic trick for me? Thanks in advance for your effort to help me
