Console Variables Editor plugin disables some CVars in Slate

The following console commands do not work when the ConsoleVariablesEditor plugin is enabled.

• Slate.GameLayer.ViewportSlotVisible
• Slate.GameLayer.DebugCanvasVisible
• Slate.GameLayer.PlayerCanvasVisible
• Slate.GameLayer.AllCanvasesVisible

Upon the investigation, since FConsoleVariablesEditorModule::QueryAndBeginTrackingConsoleVariables() runs CVarShowAllCanvases's OnChangedDelegate().AddRaw() (or AddSp() in UE5.4),  if (!CVarShowAllCanvases->AsVariable()->OnChangedDelegate().IsBound()) in SGameLayerManager::Construct() results in false and callback registration code inside the if block is not executed.

Any projects using UMG in a game can be used for reproducing. The key steps are bolded.

1. Enable Console Variables Editor plugin in Plugin window.
2. Create a project with Content Example and open it.
3. Load UMG level.
4. Run PIE.
5. Execute console command "Slate.GameLayer.AllCanvasesVisible 0"
6. Get near to each example and confirm that the UMG UIs show up even though AllCanvasesVisible are set to 0.