Epubor Ultimate is the only solution I know of that was updated to handle Amazon’s change from earlier this year. It’s a commercial package, but worth the money. It took them a couple of months to work around the last changes, but they did it. I expect they will continue to do that as needed going forward.
I am just going to places like the bay.
If it still works for you: Apprentice Alf’s DeDRM plugin for Calibre.
But I believe this ship has sailed after Amazon’s recent changes…
Did Amazon change their book format?
They changed it quite some while ago but you were still able to get books in the older format by using an older Kindle (or Kindle app version). I haven’t checked myself, but heard rumours that this loophole was closed recently.
It’s still working, set myself up the other day. You have to use a specific version of the app, an older one, and turn off Internet when installing so you can toggle the auto update off. There is a fork of Alfs code, but I just used the regular one and it was fine.
That sucks, but then again it’s par for the course for Amazon. Thanks for explaining.