message: Fix tab trapping behaviour
diff: @@ -462,7 +462,7 @@ export default class BasicMessageEditor extends React.Component<IProps, IState>
  }
  const autocompleteAction = getKeyBindingsManager().getAutocompleteAction(event);
  - if (model.autoComplete && model.autoComplete.hasCompletions()) {
  + if (model.autoComplete?.hasCompletions()) {
  const autoComplete = model.autoComplete;
  switch (autocompleteAction) {
  case AutocompleteAction.ForceComplete:
  @@ -485,7 +485,7 @@ export default class BasicMessageEditor extends React.Component<IProps, IState>
  default:
  return; // don't preventDefault on anything else
  }
  - } else if (autocompleteAction === AutocompleteAction.ForceComplete) {
  + } else if (autocompleteAction === AutocompleteAction.ForceComplete && !this.state.showVisualBell) {
  // there is no current autocomplete window, try to open it
  this.tabCompleteName();
  handled = true;
  