code: function handleActiveEditorChange(event, current, previous) {
              // Uninstall "languageChanged" event listeners on previous editor's document & put them on current editor's doc
              if (previous) {
                  previous.document
                      .off(HintUtils.eventName("languageChanged"));
              }
              if (current) {
                  current.document
                      .on(HintUtils.eventName("languageChanged"), function () {
                          // If current doc's language changed, reset our state by treating it as if the user switched to a
                          // different document altogether
                          uninstallEditorListeners(current);
                          installEditorListeners(current);
                      });
              }
  
              uninstallEditorListeners(previous);
              installEditorListeners(current, previous);
          }
docs: /*
  Handle the activeEditorChange event fired by EditorManager.
  Uninstalls the change listener on the previous editor
  and installs a change listener on the new editor.
  
  @param {Event} event - editor change event (ignored)
  @param {Editor} current - the new current editor context
  @param {Editor} previous - the previous editor context