Currently, when applying a BackgroundEffect Behavior to an Element, as part of the process, the VisualBrush of the Element will change.

However, this change to the Element's Property is not seemingly registered as part of the Undo/Redo stack.

What this results in, in consequence; is that if you have a certain colour set on an Element's 'Fill' Property, when you apply a BackgroundEffect Behavior, this colour will no longer be recoverable even if in the Undo history, you revert back to a point in time prior to the BackgroundEffect being applied.

Video Attached.

Repro Steps:

1) Create a folder in which the Studio Project will live, and place any image asset into this directory.
2) From the Studio Launcher, create a new Studio Project in the directory created in Step 1).
This will open Studio.

3) Create a MainPage.xaml, and place the prepared Image into the RootGrid of MainPage.xaml. Give this Element a custom name of 'BackgroundImage' (required).

4) Introduce an Ellipse Shape into the RootGrid, set it to 512x512, and ensure that at least a portion of the Ellipse Shape is covering the Image.

5) Select the Ellipse Shape, and navigate to the Interactivity/Behaviors tab.

6) Take a mental note that prior to the next step, the Fill Property of the Ellipse is #FFF4F4F5.

7) With the Ellipse Shape still selected, from the Interactivity/Behaviors, add to it a new BackgroundEffect Behavior

8) Select the newly-created BackgroundEffect Behavior, and in its Properties Panel, hover over the 'Source' Property, click on its 3-Dot Menu, and select 'Create Binding'.

9) Select the 'Name' tab, under the 'Element Name' Property, select 'BackgroundImage'. Then, completely clear the 'Path' field of content.

10) From the 'Effect' Property of the Behavior, select 'BlurEffect', and give it a 'Radius' of '128'.

The BackgroundImage on Stage should now blur directly under the area of the Ellipse Shape.

11) Select the Ellipse Shape from the Navigator, and inspect its 'Fill' Property.

Observe how this 'Fill' Property no longer shows the #FFF4F4F5 value observed in Step 6). (This is normal/expected)

12) Repeatedly hit Ctrl+Z to go back to a point in time where the #FFF4F4F5 is recovered.

Observe how the #FFF4F4F5 'Fill' Property is unrecoverable.

Expected Results: Changes to Element Properties are recorded in the Undo/Redo stack.