undefined

**Timeline**: Will be removed in Sveltia CMS 1.0 (expected early 2026).

**Source**: [Release v0.127.0](https://github.com/sveltia/sveltia-cms/releases/tag/v0.127.0)

---

fields:
  - label: Author Email
    name: author_email
    widget: hidden
    default: '{{author-email}}'

undefined

**Recommendation**: YAML is still preferred for better tooling support.

---

// ❌ Old (v0.117.x)
import type { SiteConfig } from '@sveltia/cms';

// ✅ New (v0.118.0+)
import type { CmsConfig } from '@sveltia/cms';

const config: CmsConfig = {
  backend: { name: 'github', repo: 'owner/repo' },
  collections: [/* ... */],
};

collections:
  - name: posts
    label: Blog Posts
    folder: content/posts
    media_folder: static/images/posts  # Collection-level default
    fields:
      - label: Featured Image
        name: image
        widget: image
        media_folder: static/images/featured  # ← Field-level override
        public_folder: /images/featured

      - label: Author Avatar
        name: avatar
        widget: image
        media_folder: static/images/avatars  # ← Another override
        public_folder: /images/avatars

undefined

---

collections:
  - name: posts
    fields:
      - label: Body
        name: body
        widget: markdown
        sanitize_preview: false  # ← Add ONLY if you trust all CMS users

slug:
  encoding: unicode-normalized
  clean_accents: false
  sanitize_replacement: '-'
  lowercase: true   # Default: convert to lowercase (v0.128.0+)
  maxlength: 50     # Default: unlimited (v0.127.0+)

collections:
  - name: config
    label: Configuration Files
    files:
      - label: Site Config
        name: site_config
        file: config.json
        format: raw  # ← NEW format type
        fields:
          - label: Config
            name: body
            widget: code
            default_language: json

fields:
  - label: Age
    name: age
    widget: number
    value_type: int/string  # Saves as "25" not 25

  - label: Price
    name: price
    widget: number
    value_type: float/string  # Saves as "19.99" not 19.99

https://yourdomain.com/admin/#/collections/posts/entries/my-post?_locale=fr

fields:
  - label: Body
    name: body
    widget: richtext  # ← NEW alias for markdown

backend:
  name: github
  repo: owner/repo
  branch: main
  base_url: https://your-worker.workers.dev  # ← Must be present

curl https://your-worker.workers.dev/health

---

collections:
  - name: posts
    folder: content/posts
    format: yaml  # or md (Markdown with YAML frontmatter)
    # NOT: format: toml

pip install yamllint
find content -name "*.md" -exec yamllint {} \;

undefined

**Step 3: Auto-fix with yamlfmt:**
```bash
go install github.com/google/yamlfmt/cmd/yamlfmt@latest
find content -name "*.md" -exec yamlfmt {} \;

undefined

**Step 2: Match format to actual files:**
```yaml

---

<!-- ✅ Correct -->
<script src="https://unpkg.com/@sveltia/cms/dist/sveltia-cms.js" type="module"></script>

<!-- ❌ Wrong - missing type="module" -->
<script src="https://unpkg.com/@sveltia/cms/dist/sveltia-cms.js"></script>

<script src="https://unpkg.com/@sveltia/cms@0.128.5/dist/sveltia-cms.js" type="module"></script>

include:
  - admin

module.exports = function(eleventyConfig) {
  eleventyConfig.addPassthroughCopy('admin');
};

media_libraries:
  default:
    config:
      max_file_size: 10485760  # 10 MB
      transformations:
        raster_image:
          format: webp  # Auto-converts to WebP
          quality: 85

fields:
  - label: Date
    name: date
    widget: datetime
    picker_utc: true  # Most flexible - outputs with timezone

fields:
  - label: Date
    name: date
    widget: datetime
    format: "YYYY-MM-DDTHH:mm:ss.SSSZ"  # Only if ALL existing dates match this format

undefined

**Prevention**:
1. Don't specify `format` if you have mixed date formats
2. Normalize all dates first before adding `format`
3. Use `picker_utc: true` instead (more flexible)

**Source**: [GitHub Issue #565](https://github.com/sveltia/sveltia-cms/issues/565), fixed in v0.126.0 (improved date parser but format strictness remains)

---

// vite.config.ts
import { defineConfig, type Plugin } from 'vite'

function ensureGDPRCompliantFonts(): Plugin {
  const fontsURLRegex = /fonts\.googleapis\.com\/css2/g
  const replacement = 'fonts.bunny.net/css'
  return {
    name: 'gdpr-compliant-fonts',
    enforce: 'post',
    transform(code) {
      if (fontsURLRegex.test(code)) {
        return code.replaceAll(fontsURLRegex, replacement)
      }
    },
  }
}

export default defineConfig({
  plugins: [ensureGDPRCompliantFonts()],
})

/*
  Cross-Origin-Opener-Policy: same-origin-allow-popups
  # NOT: same-origin (this breaks OAuth)

/*
  Cross-Origin-Opener-Policy: same-origin-allow-popups

{
  "headers": [
    {
      "source": "/(.*)",
      "headers": [
        {
          "key": "Cross-Origin-Opener-Policy",
          "value": "same-origin-allow-popups"
        }
      ]
    }
  ]
}

collections:
  - name: pages
    folder: app/(pages)
    path: "{{slug}}/page"  # ← Failed to load existing entries
    extension: mdx

collections:
  - name: root-pages
    folder: ""  # or "." or "/"
    # ← Broke when creating entries via GitHub backend

<!-- OLD: Decap CMS -->
<script src="https://unpkg.com/decap-cms@^3.0.0/dist/decap-cms.js"></script>

<!-- NEW: Sveltia CMS -->
<script src="https://unpkg.com/@sveltia/cms@0.128.5/dist/sveltia-cms.js" type="module"></script>