NotFoundError: Node.removeChild: The node to be removed is not a child of this node

**Describe the bug**
Error message appears at top of index.html where decap-cms.js is included via script tag from unpkg.com using manual CMS initialization.

**To Reproduce**
- Include decap-cms.js
- Manually initialize
- Register two events to "preSave" hook
- Call init()
- Initialize local decap server with npx decap-server
- Navigate to {localhost:port}/admin/index.html

**Expected behavior**
No error expected.

**Screenshots**
https://imgur.com/a/MjVc63H

**Applicable Versions:**
- Decap CMS version: `decap-cms@3.6.2`
- Git provider: `proxy`
- Browser version: `Mozilla/5.0 (X11; Linux x86_64; rv:136.0) Gecko/20100101 Firefox/136.0`

**CMS configuration**
```
local_backend: true
backend:
name: proxy
branch: master
commit_messages:
create: Create {{collection}} “{{slug}}”
update: Update {{collection}} “{{slug}}”
delete: Delete {{collection}} “{{slug}}”
uploadMedia: Upload “{{path}}”
deleteMedia: Delete “{{path}}”
openAuthoring: "{{message}}"
proxy_url: http://localhost:8081/api/v1
media_folder: public/uploads
public_folder: /uploads
collections:
- name: posts
label: Posts
folder: public/content/posts
create: true
slug: "{{year}}-{{month}}-{{day}}-{{slug}}"
fields:
- name: layout
label: Layout
widget: hidden
default: posts
- name: url
label: URL
widget: hidden
default: "{{slug}}"
- name: title
label: Title
widget: string
- name: date
label: Publish Date
widget: datetime
date_format: MM-DD-YYYY
default: "{{now}}"
- name: author
label: Author
widget: string
default: ""
required: false
- name: description
label: Description
widget: string
default: ""
required: false
- name: thumbnail
label: Featured Image
widget: image
required: false
- name: body
label: Body
widget: markdown
publish: true
type: folder_based_collection
sortable_fields:
- title
- date
- author
- description
view_filters: []
view_groups: []
publish_mode: simple
slug:
encoding: unicode
clean_accents: false
sanitize_replacement: "-"
isFetching: false
error: null

```

**Additional context**
index.html content:

```

Content Manager

window.CMS_MANUAL_INIT = true
const {CMS, initCMS: init} = window

CMS.registerEventListener({
name: 'preSave',
handler: ({author, entry}) => {
if (!Object.getOwnPropertyDescriptor(entry.get('data'), 'author') ||
entry.get('data').get('author').length === 0) {
let newAuth = "";

if (author && author.name) {
newAuth = author.name;
}
else if (localStorage.getItem('netlify-cms-user')) {
newAuth = JSON.parse(localStorage.getItem('netlify-cms-user'))?.name;
}
else if (author && author.login) {
newAuth = author.login;
}

if (newAuth.length === 0) {
newAuth = "Unknown Author";
}

return entry.get('data').set('author', newAuth);
}
},
});

CMS.registerEventListener({
name: 'preSave',
handler: ({entry}) => {
if (!Object.getOwnPropertyDescriptor(entry.get('data'), 'description') ||
entry.get('data').get('description').length === 0) {
const _body = entry.get('data').get('body');
let _desc = _body.length > 250 ? _body.substring(0, 247).trim() + "..." : _body;
return entry.get('data').set('description', _desc);
}
},
});

init();

```

Reproduce the error from index.html with the unpkg decap-cms.js script, two preSave listeners, manual init(), and npx decap-server. Trace the initialization and event-listener path first; done means the admin page loads without the Node.removeChild error under the reported configuration.

Written by the indexing model from the issue text.