---
title: kQLThumbnailPropertyExtensionKey
framework: quicklook
role: symbol
role_heading: Global Variable
path: quicklook/kqlthumbnailpropertyextensionkey
---

# kQLThumbnailPropertyExtensionKey

The extension to use as a badge when creating an icon.

## Declaration

```swift
let kQLThumbnailPropertyExtensionKey: CFString!
```

## Discussion

Discussion The associated value is a CFString.

## See Also

### Deprecated constants

- [kQLPreviewContentIDScheme](quicklook/kqlpreviewcontentidscheme.md)
- [kQLPreviewPropertyCursorKey](quicklook/kqlpreviewpropertycursorkey.md)
- [kQLPreviewOptionCursorKey](quicklook/kqlpreviewoptioncursorkey.md)
- [kQLPreviewPropertyAttachmentDataKey](quicklook/kqlpreviewpropertyattachmentdatakey.md)
- [kQLPreviewPropertyAttachmentsKey](quicklook/kqlpreviewpropertyattachmentskey.md)
- [kQLPreviewPropertyBaseBundlePathKey](quicklook/kqlpreviewpropertybasebundlepathkey.md)
- [kQLPreviewPropertyDisplayNameKey](quicklook/kqlpreviewpropertydisplaynamekey.md)
- [kQLPreviewPropertyHeightKey](quicklook/kqlpreviewpropertyheightkey.md)
- [kQLPreviewPropertyMIMETypeKey](quicklook/kqlpreviewpropertymimetypekey.md)
- [kQLPreviewPropertyPDFStyleKey](quicklook/kqlpreviewpropertypdfstylekey.md)
- [kQLPreviewPropertyStringEncodingKey](quicklook/kqlpreviewpropertystringencodingkey.md)
- [kQLPreviewPropertyTextEncodingNameKey](quicklook/kqlpreviewpropertytextencodingnamekey.md)
- [kQLPreviewPropertyWidthKey](quicklook/kqlpreviewpropertywidthkey.md)
- [kQLThumbnailPropertyBadgeImageKey](quicklook/kqlthumbnailpropertybadgeimagekey.md)
- [kQLThumbnailPropertyBaseBundlePathKey](quicklook/kqlthumbnailpropertybasebundlepathkey.md)