This is the function of the Contents toolbar components from the left:
* pop-up button - opens the pop-up menu (same as right-click or Alt+F10)
* go to button - go to the currently selected element
* split button - open second Contents window for drag-and-drop operations
* hook button - set the currently selected element as the hook of the currently active category (the one displayed in category combo box on the toolbar in the main window of full SuperMemo
* collapse button - collapse the branch with the currently selected element
* large synchronize button - synchronize the contents of the element window with the current selection in the Contents window
* small synchronize button - synchronize the contents of the item data window with the current selection in the Contents window
* drag-and-drop combo - determines what drag-and-drop operation is currently active (the operations available: Replace the target - moves the source element to the place of the target element, Add as last child - moves the source to the last child of the target, Add as last sibling - moves the source to the last sibling of the target, Transplant children - moves all children of source and adds them as children of the target, Transplant partly - same as Transplant children but only a subset of children is moved)
* search button - search for a substring among expanded branches of the hierarchy
* commit, reset and dismiss buttons - commit, reset or dismiss all children or all descendants of the currently selected element
* save button - save the currently expanded nodes as a text file
* info button - displays element information (this button is only available in the debugging SuperMemo; see Tools : Options : Data access : Debugging version)