Automated bamboo farm built in previous beta collects bamboo in minecart with hopper. However, activate/right-click on hopper does not open GUI showing items. Breaking minecart drops items collected, and creating a new minecart with hopper allows you to open GUI as long as the hopper is empty.
This does not affect ordinary hoppers, that I can tell.
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We're tracking this issue as MCPE-63901, so this ticket is being resolved and linked as a duplicate.
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