The field changed in the widget blueprint replaces the actual value from the bound C++ widget class

Development Programming & Scripting C++
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There are two widgets - ParentWidget and ChildWidget. ChildWidget is created inside ParentWidget. Both of that widgets are bound to the UUserWidget child class. ChildWidget has bool flag bBoo with UPROPERTY(EditAnywhere) specifier, so it can be changed either from the editor UI or from the C++ logic, so far so good.
I make bBoo=true through the editor UI, and, after some time, I reset it back to false through the C++ logic. To make it clear, bBoo is always gets the value true from the editor UI and false from the C++ code, and all changes are made in the editor, without starting the game.
Here the strange behavior:
When later I select this widget in editor UI, bBoo=false (as it should be), but after changing the position of the ChildWidget - flag bBoo changes back to true . It seams that the widget blueprint caches fields, and prefers changes from the UI over changes from bound C++ class.

To sum up, all steps looks like this:

  • Change bBoo=true in the editor
  • At some point bBoo=false in C++ logic
  • Move ChildWidget (bBoo displays as false as it should be)
  • After releasing the mouse bBoo changes back true by itself (last assigned value from editor)

Here are some conclusion from my attempts:

  • Adding Transient specifier only makes it worse, so the bBoo field always resets to false after moving the ChildWidget
  • Adding ExposeOnSpawn=true meta doesn’t affect anything
  • InvalidateLayoutAndVolatility() doesn’t affect anything
  • NativeConstruct() doesn’t fire, because all actions are made in the editor, without starting the game.
  • PostEditChangeProperty() method doesn’t help, because the value set from C++ already has a lower priority than the value from the editor.

Is it possible in C++ code to clear widget’s cache after changing the bBoo flag, or force it to refresh its cache?

This problem is also relevant for other fields. For example, the position of the ChildWidget
So, ObtainedPosition returns the last “dragged” position in editor, but not the ExpectedPosition from the example

Cast<UCanvasPanelSlot>(ChildWidget->Slot)->SetPosition(ExpectedPosition);
// ...
const FVector2D ObtainedPosition = Cast<UCanvasPanelSlot>(ChildWidget->Slot)->GetPosition();