v10.0.21

I have attempted to create a variation of KFXArchiver for MS Store version of the K4PC app (MSIXKFXArchiver1_15230.exe). Supported version in the name. Use link generator if MSStore does not give you the app for whatever reason, or figure out powershell.
The important differences and caveats are as follows:

• The tool creates a folder on your C: drive (C:\Data), and copies temp data there. That includes the whole of the installation of the App since for whatever reason I cannot read the dlls without copying them first. So that is about ~800MB of free space necessary (folder can be deleted after tool is done)
• Command line is mostly the same as KFXArchiver, without the fourth (version switcher one), but now they have defaults, so book folder defaults to the content folder of the app (c:\Users\User\AppData\Local\Packages\AMZNKindle.AmazonKindleReadingApp_xxxxx\LocalState\Classic\Content\), output folder defaults to archived_kfx and k4i file to oldbooks.k4i. if keyword default is used for value, it will pull from defaults. It can be run without any arguments at all, as well.
• It attempts to make a fake book and read it for secrets, so hopefully getting free books will not be necessary
• Probably other things that I don't remember
• As usual, works for me, may not work for thee, and provide the output of the tool if you are asking for help, please.

In addition, the artifacts of this release include kfxdedrm_kual.zip. It is a KUAL extension for jailbroken Kindles, which was tested on a variety of devices, so I am mostly satisfied, though I expect edge cases. It works better with KOReader since it uses output tool from it. But should work either way. Its default mode does need space for decrypted books, though, so be careful and maybe go into airplane mode before running it.

Note: The python version plugin did not have any real changes for this release.
Edit: the issue with running it from non-C: paths should be fixed. Now it should generate Data folder depending on where it is run from
Edit 2 (2026/06/11): replaced copying folder with explicit file lists, hopefully would help with some encrypted file setups.
Also, @jadehawk, you might be interested, so I am tagging you.