Fortune 3 doesn't work at all in the Beta 1.16.0.55.
Expect when mining ore's with Fortune 3:
It give multiple items from the block affected by Fortune 3.
What really happens:
You get the normal amount of items, basically 1 diamond every time when mining diamond ore with Fortune 3.
Thank you for your report!
We're actually already tracking this issue at MCPE-67169, 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.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
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