Shearing a sheep or mooshroom in survival works once when the durability of the shears is perfect, but after that when the green durability bar appears, the Shear button will not appear and only comes back if you repair the durability back to 100%.
The shears work fine on grass and leaves despite this bug. In creative, they also work fine, unless you convert from survival to creative with damaged shears in your inventory. Then those shears keep their damage (but the green bar disappears) so you have to drop those shears and get another from the creative inventory for them to work again.
Linked issues
is duplicated by 8
MCPE-18533
You can not take wool out of the sheep !!! (Cannot Shear Sheep + Others With Used Shears)
Resolved
MCPE-18558
Sheep shearing is broken in 17.02 alpha. You can a sheer a sheep once with shears then, even when a sheep eats, you cannot shear them again unless you use a new shear.
Resolved
MCPE-18597
A tesoura na trabalha
Resolved
MCPE-18695
Can't sheer sheep
Resolved
MCPE-18728
Can not shear sheep
Resolved
3 more links
Comments 5
Interestingly, this bug does not affect 0.16.2. So it looks like it must have gotten broken again in the 1.0 beta.
Reopening, affects 0.17.0.* beta