Bug 275171 [Contributions] Customize Perspective action breaks editor pinning action
Using M7, I enabled editor pinning (i.e. Reuse editor) and pinned an editor using an action in the toolbar. I then disabled editor pinning ad then opened the customized perspective dialog. After this, enabling/disabling editor pinning does not make the Pin Editor action reappear.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/WorkbenchActionBuilder.java
private IWorkbenchAction maximizePartAction;
    
    private IWorkbenchAction minimizePartAction;
    private IWorkbenchAction switchToEditorAction;
	private IWorkbenchAction workbookEditorsAction;
    private IWorkbenchAction quickAccessAction;
    private IWorkbenchAction backwardHistoryAction;
    private IWorkbenchAction forwardHistoryAction;
    
    private IWorkbenchAction undoAction;
    private IWorkbenchAction redoAction;
    private IWorkbenchAction quitAction;
    private IWorkbenchAction goIntoAction;
    private IWorkbenchAction backAction;
    private IWorkbenchAction forwardAction;
    private IWorkbenchAction upAction;
    private IWorkbenchAction nextAction;
    private IWorkbenchAction previousAction;
    
    private IWorkbenchAction openWorkspaceAction;
    private IWorkbenchAction projectPropertyDialogAction;
    private IWorkbenchAction newWizardAction;
    private IWorkbenchAction newWizardDropDownAction;
    private IWorkbenchAction importResourcesAction;
    
    private IWorkbenchAction exportResourcesAction;
    IWorkbenchAction buildAllAction; 
    private IWorkbenchAction cleanAction;
    private IWorkbenchAction toggleAutoBuildAction;
    MenuManager buildWorkingSetMenu;