A powered minecart's furnace is always facing west when driving from west to east or from east to west,
when driving from north to south, or south to north, the furnace is always facing north.
When making a circle or tracks, this will result in the furnace flipping at specific corners.
Tested in Creative, but I suspect it also to happen in Survival.
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Duplicate of MC-9551, please use the search function to see if your bug has already been submitted. Currently over 55% of tickets are being closed as duplicate.
Did search, but for powered minecarts, no result found back then, sorry.
Because it duplicates a minecarts issue, but you looked for powered minecarts only...