message: Fix bug that inserted emoji when typing
  This was quite simple in the end -- the mouse doens't move, but on some browsers, the autocomplete appearing beneath the mouse would cause the `onMouseOver`, which is not `onMouseMove`.
  The fix was to use `onMouseMove`.
  Fixes vector-im/riot-web#4974
diff: @@ -233,7 +233,7 @@ export default class Autocomplete extends React.Component {
  const componentPosition = position;
  position++;
  - const onMouseOver = () => this.setSelection(componentPosition);
  + const onMouseMove = () => this.setSelection(componentPosition);
  const onClick = () => {
  this.setSelection(componentPosition);
  this.onCompletionClicked();
  @@ -243,7 +243,7 @@ export default class Autocomplete extends React.Component {
  key: i,
  ref: `completion${position - 1}`,
  className,
  - onMouseOver,
  + onMouseMove,
  onClick,
  });
  });
  