Are you doing anything cool to take advantage of running PostmarketOS? I've thought for a while it would be nice to have a simple writing environment on my clara HD with an external keyboard.

There's also this interesting project: https://github.com/Quill-OS/quill

Yes, but also a reminder that those older, well supported ones are Freescale i.mx. After that, Kobo used Allwinner from sunxi (who have a general history of GPL violations) and now something from Mediatek (who had a history of not providing good driver update support). Those are likely completely different, might need a lot of new work to properly get a kernel running on, let alone mainline. Who knows if the bootloader can even be unlocked this time?