message: WIP to prevent RTE from deleting current message input when up arrow pressed
diff: @@ -560,7 +560,7 @@ export default class MessageComposerInput extends React.Component {
  onUpArrow = async (e) => {
  const completion = this.autocomplete.onUpArrow();
  - if (completion == null) {
  + if (completion == null && !(this.historyManager.currentIndex === -1 && this.state.editorState.getCurrentContent().hasText())) {
  const newContent = this.historyManager.getItem(-1, this.state.isRichtextEnabled ? 'html' : 'markdown');
  if (!newContent) return false;
  const editorState = EditorState.push(this.state.editorState,
  @@ -575,7 +575,7 @@ export default class MessageComposerInput extends React.Component {
  onDownArrow = async (e) => {
  const completion = this.autocomplete.onDownArrow();
  - if (completion == null) {
  + if (completion == null && !(this.historyManager.currentIndex === -1 && this.state.editorState.getCurrentContent().hasText())) {
  const newContent = this.historyManager.getItem(+1, this.state.isRichtextEnabled ? 'html' : 'markdown');
  if (!newContent) return false;
  const editorState = EditorState.push(this.state.editorState,
  