WorkflowProcessor.MyForm_OnBackClicked nullify myConflictsPage without disposing it. This leads to Solution leak, because tree control doesn't unsubscribe from look and feel changing event. ESP:b41f650:Root:02b0f834(JetBrains.VSIntegration.Shell.VSAddInShell)-> 02af2200(System.Threading.Thread)-> 32a2f2cc(System.Object[][])-> 02af22ec(System.Object[])-> 02d95904(DevExpress.LookAndFeel.UserLookAndFeelDefault)-> 410f2e20(System.EventHandler)-> 410f2d90(System.Object[])-> 37348530(System.EventHandler)-> 37348508(DevExpress.LookAndFeel.Helpers.ControlUserLookAndFeel)-> 37348364(DevExpress.XtraTreeList.Scrolling.VTLScrollBar)-> 37341da4(JetBrains.ReSharper.Refactorings.Workflow.WinForms.ConflictsTreeList)-> 37341738(System.Windows.Forms.Panel)-> 37340bac(JetBrains.ReSharper.Refactorings.Workflow.WinForms.ConflictsPage)-> 3732e074(JetBrains.ReSharper.Refactorings.Workflow.WinForms.WorkflowProcessor)-> 0cddaba4(JetBrains.ProjectModel.Impl.SolutionImpl)