When in the creative inventory you will see the dyes section... In it there is all the dyes including brown. The brown dye is also right next to the dyes section, but it's titles Cocoa Beans.
The Cocoa Beans have the texture of brown dye.
MCPE-39617
Dyes in the Inventory
Resolved
Cannot Reproduce
0
Thank you for your report!
However, this issue has been closed as Cannot Reproduce.
We were unable to reproduce the problem you are describing in the latest version.
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