Installers for older versions are becoming increasingly elusive, I've found. Anything newer than Kindle for PC v1.26 and DeDRM can't break the encryption. Installers for v1.17 or v1.19 can still be found, but on Linux those versions can't connect to Amazon because one of the SSL certs used by the app has expired.

That leaves v1.21 as the "sweet spot", but most of the sites that used to host that installer EXE have mysteriously disappeared.

You can get the missing certificate from the links in https://forums.linuxmint.com/viewtopic.php?f=47&t=342186&uid... .

That workaround gets you the text but it's missing a lot of the recent typographic improvements. It's fine for extracting text for TTS, but isn't ideal if what you are trying to do is maintain a DRM free archive of books you've purchased.

It's like saying you can break BluRay DRM by recording the screen with your phone camera.

What kind of typographic improvements do you have in mind?

Stuff like drop caps, kerning that isn't terrible, hyphenation, and better word spacing. None of it matters if you are feeding the text to a speech synthesizer, but it can make a difference when reading.

Some of that stuff you can get back by using an ePub version and reader from the AZW3 file which can typically be done using KindleUnpack. Some of it is less the file format and more the rendering engine used and they simply haven't bothered to backport it to their AZW3 renderers. Amazon does AFAIK precompute some stuff like hyphenation but not everything.

The point is the KFX format does have all that natively.

And my point is that some of it not native (it's handled by the renderer) and it's possible to get back or similar enough (precomputing hyphenation).

If you're willing to do a bunch of work, you may be able to recreate something close to the original KFX. AFAIK you won't get kerning though. That seems to be tied to the renderer used for KFX files.

The other part is that there isn't a single definitive KFX file for a title. If you have an Oasis and I have a Paperwhite and we both download the same book, I believe we get different KFX files. There's no reason to doubt that there will be future Kindle devices that are even better with respect to typography and so you will need to re-download your library for that device.

Today, KFX can sometimes be De-DRM'd but it's gotten to the point where it's a cat and mouse game. It works for a while then Amazon changes something and breaks it. I don't doubt that essentially uncrackable DRM is achievable.

The real fix is legislative.