Please excuse my lack of Knowledge dealing with Jira, just started using the platform per today.
Now, The issue with the Achievement "Rainbow collection" on Xbox one has not Yet been resolved as of update 1.12.0.10.
This bug has been ongoing since creating our Friendly multiplayer world back 3 months ago, We've tried mostly everything we can to earn this achievement, but to no avail.
Placing the wool in a single chest, Double chest, dropping them 1 by 1 into our inventory, Placing them in the hotbar, using dispensers to shoot them at us, everything.
I'm not sure if the game is Detecting whether or not the wool needs to be sheared from Natural spawned Sheep, or if dying them the colors you need matters.
Thank you for your report!
We're actually already tracking this issue at MCPE-30718, so we will resolve and link 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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