when shifting and right clicking with chest on donkey not working

*What I expected to happen was when shifting and right clicking with chest on donkey it will put it on it

*What actually happened was when shifting and right clicking with chest on donkey you start to ride the donkey and it not put it on it

Steps to Reproduce:
1. find a donkey (i know its rare but give it a try or spawn one) you can find horses and donkeys in plane byomes
2. try shift and place chest on it
3. see that its not working (how i now have a ridable inventory)