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Note that the thumbnails for existing assets are not automatically re-generated. If the existing thumbnails should be re-generated, this can be done by setting up an automation that uses the “Generate asset renditions” step with the “Force generate” flag enabled.
Since the file type of the thumbnails has been changed, the asset streamer returns the response header Content-Type: image/webp instead of the correct response header Content-Type: image/jpeg for existing thumbnails. Most browsers should be able to display the thumbnails despite of this. If it becomes an issue, the existing thumbnails can either be re-generated as described above, or the thumbnail formats can be modified to be of the type jpeg.
Source formats
The new transcode system now supports a special SourceFormat that can be used to refer to and get the source files of assets. A special “Original” format of this type is now defined out-of-the-box. If you have previously hard-coded the “Original” format in a list of available download qualities, this can lead to two “Original” formats being shown. It should no longer be necessary to have any special-case handling for getting source formats.
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