Can't rename a parameter in Animator Parameters

When I go to Windows → Animator Parameters, I can not rename the parameter anything else then its default, “New Int”. I pressed the add button and selected Int. Then when I click on the parameter with the default name “New Int” on it, the default name disappears, and I can’t type anything in there. If I click on it again, an error message comes up saying “BeginRename fail: already renaming” Please help. Thank you.

I think I have the same issue as you. While I still can’t change names in Window → Animation Parameter, but this worked for me:

Instead, set/change parameter names through Window → Animator, and (in that window) switch from the Layers tab to the Parameter tab. That menu looks the same, but actually works (for some reason).

Hope this helps!

This is a bug in Unity 2020.1.0b3.3385

IndexOutOfRangeException: Index was
outside the bounds of the array.
(wrapper stelemref)
System.Object.virt_stelemref_class_small_idepth(intptr,object)

After experimenting with the bug I found that the last change made before saving the project will always be reverted by Unity (because it’s out of range) so if you make two parameters, rename the first and then save the project you can call your parameters what you want, instead of New Whatever. You can then delete the useless ones and the behaviour list will not rename them when selecting them.