Whilst trying to fill ponds rivers or just use bucket of water in general the click point on the surface is all wrong. it sometimes adds water to the surface instead of the man made pond it also lets out water randomly sometimes
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Thank you for your report. This issue was, however, submitted earlier as MCPE-17417. Please perform a search next time to make sure your bug hasn't already been reported. The parent issue can easily be found by searching for "mcpe unresolved bucket".