@darius There are some important limitations on the DeDRM Kindle plugin now. If you have a physical E-ink Kindle device then you can pull the book files off your Kindle and convert them in calibre. You need to enter your Kindle’s serial number in the DeDRM settings somewhere. Kindle for Mac and Kindle for PC are a tougher proposition. They still work but only under certain conditions. A new installation on Catalina will certainly not work. An older 32-bit Kindle for Mac does, with effort.