Area Nodes body_shape_entered signal returns wrong body_shape index

[19PHOBOSS98]

Godot version:
3.2.1
OS/device including version:
Macbook Pro 10.15.2
Issue description:
I had a static body with more than two shapes. The area node moves around with the player. The node detects the static body just fine but it keeps returning a body_shape index of 0 regardless of which collision shape it detects. Is this a bug or am I doing something wrong?
Steps to reproduce:
-add a scripted area node with the "entered_body_shape" signal pointed to the script and parent it to an avatar
-create a static body with two or more collision shapes
-collide with said collision shapes using player's area node
-read out returned value of parameter "body_shape"

Minimal reproduction project:

Wrong Body Shape Index.zip

[Calinou]

Duplicate of #19290. As a workaround, switch to the GodotPhysics engine instead of Bullet in the Project Settings.