I play with a Xbox one controller on my Windows 10 pc.
I use custom setting like: switching items in hot bar with dpad instead of bumpers.
Minecarts doesn't respect this setting once I am in a minecart the controlls work like I never changed them, once I leave the minecart controls work as I have set them.
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-20463.
Your additional information and observations are very useful, so if you can add them to the comments section of the parent issue it would be appreciated.
If you have not, you might like to make use of the search feature before making a new ticket, as it's likely that the issue has been reported already.
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