@rjsf/mui@6.0.1 breaks layouts with nested forms

[Robbilie]

Prerequisites

• I have searched the existing issues
• I understand that providing a SSCCE example is tremendously useful to the maintainers.
• I have read the documentation
• Ideally, I'm providing a sample JSFiddle, Codesandbox.io or preferably a shared playground link demonstrating the issue.

What theme are you using?

mui

Version

6.0.1

Current Behavior

widths and alignments of various elements are broken

Expected Behavior

layouting behaves the same as in 5.24.13

Steps To Reproduce

Playground

Environment

no compile, run in browser

import React, { useEffect, useState } from 'https://esm.sh/react@19.2.0';
import { createRoot } from 'https://esm.sh/react-dom@19.2.0/client';

import $RefParser from 'https://esm.sh/@apidevtools/json-schema-ref-parser@14.2.1';

import Form from 'https://esm.sh/@rjsf/mui@5.24.13';
import validator from 'https://esm.sh/@rjsf/validator-ajv8@5.24.13';


replacing the versions with 6.0.1

Anything else?

No response