message: Register more image file formats for the ImageBlock extension
diff: {
  "name": "image-block",
  "mimeTypes": [
  - "image/png"
  + "image/png",
  + "image/gif",
  + "image/jpeg",
  + "image/x-portable-bitmap",
  + "image/x-portable-graymap",
  + "image/x-portable-pixmap",
  + "image/x-portable-anymap",
  + "image/x-xbitmap",
  + "image/x-xbm",
  + "image/x-xpixmap"
  ]
  }
  ],
  