clickCount accumulates without reset when mouse button changes without movement

GoJS
1

**GoJS version**: 1.8.38

When clicking the canvas without moving the mouse between clicks, `InputEvent.clickCount` keeps accumulating across different mouse buttons. This causes `BackgroundContextClicked` (and other click events) to never fire after `BackgroundDoubleClicked`.

**Reproduction**:

1. Double-click on background → `BackgroundDoubleClicked` fires (clickCount=2) ✅

2. Without moving the mouse, right-click → no event fires (clickCount=3)

3. Subsequent right-clicks: clickCount=4, 5, 6… still no event

**Logs from `toolManager.doMouseDown` wrapper**:

```

doMouseDown {btn: 0, clickCount: 1}

doMouseDown {btn: 0, clickCount: 2}

→ BackgroundDoubleClicked

doMouseDown {btn: 2, clickCount: 3} ← right-click after dblclick, no event

doMouseDown {btn: 2, clickCount: 4} ← still accumulating

doMouseDown {btn: 2, clickCount: 5}

```

**Things tried (without success)**:

- Setting `lastInput.clickCount = 1` directly in a doMouseDown override (assignment is accepted but ignored by GoJS internal counter on next click)

- Dispatching synthetic `mousemove` events on the canvas DOM (with offset coordinates)

The behavior seems intentional for multi-click gestures (triple/quadruple clicks), but treating a button switch as part of the same sequence is surprising. Native browsers reset `event.detail` when the button changes.

**Questions**:

1. Is there an official way to reset the click sequence from user code?

2. Could the click sequence detection consider mouse button changes as a sequence boundary?

Thanks!

2

I just tried this, and was unable to reproduce a problem. What am I doing wrong to try to reproduce what you are reporting?

<!DOCTYPE html>
<html>
<body>
  <div id="myDiagramDiv" style="border: solid 1px black; width:100%; height:400px"></div>

  <script src="https://cdn.jsdelivr.net/npm/[email protected]"></script>
  <script id="code">
const $ = go.GraphObject.make;
const myDiagram =
  $(go.Diagram, "myDiagramDiv", {
      "BackgroundDoubleClicked": e => console.log("Double", e.diagram.lastInput.clickCount, Date.now()),
      "BackgroundContextClicked": e => console.log("Context", e.diagram.lastInput.clickCount, Date.now()),
    });
  </script>
</body>
</html>