Detect when the window is still captured when dragging was aborted for some reason

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@73355 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/richtext/richtextctrl.cpp

@@ -751,6 +751,14 @@ void wxRichTextCtrl::OnLeftUp(wxMouseEvent& event)
 /// Mouse-movements
 void wxRichTextCtrl::OnMoveMouse(wxMouseEvent& event)
 {
+    if (!event.Dragging() && m_dragging)
+    {
+        // We may have accidentally lost a mouse-up event, especially on Linux
+        m_dragging = false;
+        if (GetCapture() == this)
+            ReleaseMouse();
+    }
+
 #if wxUSE_DRAG_AND_DROP
     size_t distance = 0;
     if (m_preDrag || m_dragging)