message: same behaviour on delete
diff: @@ -242,10 +242,10 @@ function createOnKeyDown(
  if (!slateClosure.current) return
  if (isValueEmpty(editor.value)) {
  // focus previous plugin and remove self
  - const { remove } = slateClosure.current
  + const { remove, focusPrevious } = slateClosure.current
  if (typeof remove === 'function') {
  - if (typeof slateClosure.current.focusPrevious === 'function') {
  - slateClosure.current.focusPrevious()
  + if (typeof focusPrevious === 'function') {
  + focusPrevious()
  }
  remove()
  }
  @@ -267,6 +267,16 @@ function createOnKeyDown(
  if (key === 'Delete' && selectionAtEnd(editor)) {
  if (!slateClosure.current) return
  + if (isValueEmpty(editor.value)) {
  + // focus previous plugin and remove self
  + const { remove, focusNext } = slateClosure.current
  + if (typeof remove === 'function') {
  + if (typeof focusNext === 'function') {
  + focusNext()
  + }
  + remove()
  + }
  + } else {
  const { mergeWithNext } = slateClosure.current
  if (typeof mergeWithNext !== 'function') return
  @@ -277,6 +287,7 @@ function createOnKeyDown(
  .insertFragmentAtRange(selection, value.document)
  .select(selection)
  })
  + }
  return
  }
  