Attributes are reset to the default ones

What behaviour is expected:

When I add unique attributes to a wolf, they stay with it forever
I wanted to implement a system for passing attributes by inheritance, but it works with all mobs except wolves

What behaviour is observed:

I added attributes to the wolf, but after it became angry - all attributes were reset to the default ones (also works with taming)

Steps/models to reproduce:

VIDEO pay attention to the chat-debug
I just set the entity attributes.

UPD: 

Anything else:

For some reason, this works with a cat, but it doesn't work with a wolf
At first I thought it was a server-core bug, but the developer told me it was a vanilla thing 😞