Chests in minecarts have their lighting determined by the light level of where you are standing. Sorry if you canโt see the chest in some pictures, I could not get a video.
Steps to reproduce:
Place a chest minecart in a dark or well-lit area
Move yourself to different light levels as you look at the chest
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Thank you for your report!
We're actually already tracking this issue at MCPE-22533, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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