message: Explicitly prevent :help command
diff: @@ -47,6 +47,11 @@ class CommandLine {
  command = command.slice(1);
  }
  + if (command === 'help') {
  + StatusBar.Set(`:help Not supported.`, vimState.currentMode, vimState.isRecordingMacro, true);
  + return;
  + }
  +
  this._history.add(command);
  this._commandLineHistoryIndex = this._history.get().length;
  