Multiple fill: Undo does not work

[dominik]

1. Create a new document and add one vector object, e.g. a rectangle.
2. Make sure 'Appearance Panel' is visible and click on 'Add Fill'.
3. Assign the new fill some colour by clicking on the round icon.
4. Right click on the under most fill and select 'Delete'.
5. In History Panel step one undo back or hit CTRL+Z.

Expected behaviour: the previously deleted fill is restored.
Observed behaviour: the last fill in the list changes its fill to the colour of the deleted fill.

I made a screen recording. I hope you can follow and recreate this.

d.

PS: it may be necessary to click on the GIF-animation to see the animation.