I request an option for a user to downdate the e.foundation version using a sdcard or usb-stick.
The e.foundation downdate, or an update if you are brave (wlan in moto g5 cedric fails, and I gues nobody tested the version 1.21r with a real device) is stored on sdcard.
The user selects it with a file browser and selects update. The Version and hash values of the firmware file are shown and the user shall confirm them against hash values shown on the download page.
If the firmware does not belong to the hardware a warning shall be produced and the update shall be blocked with an override option which is protected by entering a mantra of 23 letters.
The user selects install firmware (update or downdate depending on version on sdcard)
This update / downdate shall be possible without loosing apps and data!
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