[Lexical] `TextStateFeature` State key collision error with nested editors

[elliott-w]

Describe the Bug

When two different editors use the same TextStateFeature config:

We get client-side error:

Lexical.dev.mjs:20 Uncaught Error: $setState: State key collision "color" detected in TextNode node with type text and key 18. Only one StateConfig with a given key should be used on a node.
    at StatePlugin.useEffect (textState.ts:62:40)
    at Map.forEach (<anonymous>)
    at StatePlugin.useEffect (textState.ts:61:20)
    at StatePlugin.useEffect (textState.ts:46:31)

Link to the code that reproduces this issue

https://github.com/elliott-w/payload/tree/bug-text-collision

Reproduction Steps

Here's the editor config:

import {
  BlocksFeature,
  InlineToolbarFeature,
  lexicalEditor,
  TextStateFeature,
} from '@payloadcms/richtext-lexical'
import { type Block } from 'payload'

const CustomTextStateFeature = TextStateFeature({
  state: {
    color: {
      red: {
        label: 'Red',
        css: {
          color: 'red',
        },
      },
    },
  },
})

const testBlockEditor = lexicalEditor({
  features: [CustomTextStateFeature, InlineToolbarFeature()],
})

const TestBlock: Block = {
  slug: 'testBlock',
  fields: [
    {
      name: 'contentNested',
      type: 'richText',
      editor: testBlockEditor,
    },
  ],
}

export const fullEditor = lexicalEditor({
  features: [
    CustomTextStateFeature,
    InlineToolbarFeature(),
    BlocksFeature({
      blocks: [TestBlock],
    }),
  ],
})

Which area(s) are affected? (Select all that apply)

plugin: richtext-lexical

Environment Info

Binaries:
  Node: 23.11.0
  npm: 10.9.2
  Yarn: N/A
  pnpm: 9.7.1
Relevant Packages:
  payload: 3.54.0
  next: 15.4.4
  @payloadcms/db-postgres: 3.54.0
  @payloadcms/live-preview-react: 3.54.0
  react: 19.1.0
  react-dom: 19.1.0
Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 24.6.0: Mon Jul 14 11:30:40 PDT 2025; root:xnu-11417.140.69~1/RELEASE_ARM64_T8132
  Available memory (MB): 16384
  Available CPU cores: 10