You may get streaking or bad colors when updating the image. Flushing the display by writing a solid color can kinda work, but not reliably. This seems to happen when the display is always-on via a USB connection, and not until the display has been powered this way for months. Switching to a battery pack seems to solve the issue: https://forums.pimoroni.com/t/inky-frame-7-3-burn-in/24574/7
The Inky Frame 5.7 doesn't seem to have this issue.
MicroPython can be finicky with SD cards. The brand matters a lot. Big name brands seems to work better than no-name or generic brands.The failure will happen at the sdcard.SDCard line where the card is mounted via the GPIO pins.
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