mouseLeave issue with gojs 2.2.21 update

GoJS
1

MouseLeave problem appeared with Gojs 2.2.21 update. I think it occurs with bug fixed in 2.2.20 update

“Corrected [GraphObject.mouseLeave] sometimes not getting called when the user’s pointer leaves the Diagram”

2

Did you have a question?

3

mouseover works after hovering over the image, even though I do nothing, mouseLeave is triggered

goMake(go.Picture, Tools.ExclamationShape,
                        {
                            name: "ErrorIcon",
                            desiredSize: new go.Size(16, 16),
                            alignment: go.Spot.TopRight,
                            mouseHover: (e: go.InputEvent, obj: go.GraphObject) => {
                                if (obj && obj.part && obj.part.data) {
                                    this.showErrorMessages(obj.part.data.key);
                                }
                            },
                            mouseLeave: () => {
                                this.hideErrorMessages();
                            }
                        },
                        new go.Binding("visible", "", (val: any, obj: any) => {
                            return this.validationMessages.find((x) => x.itemKey === obj.part.data.key) ? true : false;
                        }),

                    ),
4

What does showErrorMessages do?

5 
showErrorMessages(key?: string) {

        if (this.validationMessages.find((i) => i.itemKey === key)) {

            this.setState({ lastMouseOverKey: key });

            if (this.errorMessagesDiv) {

                let pt = this.diagram.lastInput.viewPoint;

                this.errorMessagesDiv.style.left = (pt.x + 10) + "px";

                this.errorMessagesDiv.style.top = (pt.y + 10) + "px";

                this.errorMessagesDiv.style.display = "block";

            }

        }

    }
6

Is that Div placed in a manner where the mouse would no longer be in the Diagram but in that Div instead? That would warrant a mouseLeave event.

Note that InputEvent.viewPoint is in view coordinates (i.e. the Diagram.div’s coordinates), not client or page or screen coordinates.