WysiwygEditor has some undocumented theme dependancies

[aryzle]

Summary

Using WysiwygEditor like the docs suggest errors

Steps to reproduce

try to use https://remirror.io/docs/showcase/richtext in your React app

Expected results

The Wysiwyg Editor to render and work

Actual results

errors inside of Mui components that are used in the Wysiwyg Editor due to theme

Possible Solution

This was the minimum I needed to add to my theme to get this to work

import { extendTheme } from '@mui/joy/styles'

export const theme = extendTheme({
  ...
  shape: {
    borderRadius: 8,
  },
  palette: {
    action: {
      active: '#ffffff',
    },
    Tooltip: {
      bg: '#121416',
    },
  },
})

Screenshot(s)