not 100% libre but better alternatives...
Search for boox. They come in all sizes. But not in FLOSS philosophy
It's not libre, but I would recommend Kobo as the "least worst" alternative.
It's very easy to sideload anything, the devices are nice to use and the built-in store has some DRM-free books available (though it's mostly DRM stuff).
For more technically-minded people there are also various projects giving Kobos totally libre unofficial firmware.
@rgggn Tolino uses OSS only, I am not sure about the F though. Also there might be an exception for the stuff opening DRM-infested pdfs.
But it runs on android, so you can root it (german article, but nice syntax so it should be machine-translatable with a reasonable quality).
If it's in budget I'd recommend the vision 4 HD model for its support for redshift-like behaviour. (Also I can't judge about the rest since I only ever had a vision 4 HD in my hands.)
@rgggn older Kobo's have some alternate completely libre firmwares floating around on github. (sans wifi firmware blobs) Their not entirely feature complete, but good enough for simple eReading.
Between that and tripping over a few PDFs and ePubs that crash the koreader build it ship with Ive switched back to the proprietary firmware, but using a hostfile hack to block all the tracking services on the device.
Hoping to try again with future releases.
@rgggn Try Onyx
@rgggn i don't think duokan is foss tho
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