Animation is going crazy when changing Image material

Hey,

I’ve just upgraded to 2019.1. Sadly, I just figured out that you can’t change Image material key via animation, because it literally breaks the animation. I’m pretty sure that this is a bug, but is there any fix that issue? Happens with 2019.2 alpha as well.

As you can see, ‘New Game Confirm’ value is 40, and stays like that till the end. Normally, you can’t go higher than 1. ‘Background Blur’ is changing the material of image. If I delete this, it’ll play normally.

What are you trying to do exactly? Is it really nessesary to change material via animation?