I want to add http://books-by-isbn.com/
to the plugin but I can't find where to add it
I've added a couple of sites in the past but can't remember how I did it. Clicking on Customize plugin, I only get an alert "doesn't need customization".
The same with the "Open in Sigil" plugin. I remember I customized it by entering the path to the Sigil executable but can't remember where I did it.
I guess my memory is not what it used to be