Metadata loss converting png->jxl->png

[thequver]

Version

1.2.2

OS

Windows

Description

Hello, I encountered a problem while converting comfyui output png images into a jxl. I encoded the image then used jpeg reconstruction +png fallback to restore the original image. The metadata comfyui uses to save its workflow is lost on both encoder-preserve or exiftool-preserve options. It looks like this in exiftool gui:

An image example containing the metadata:

Steps to Reproduce

1. Set encoder-preserve or exiftool-preserve in the app settings
2. Try to convert an example image into jxl
3. Restore the image back to png
4. Check the metadata

Expected Result

Metadata is preserved

Current Result

Metadata is lost

Input Formats

png

Selected Format / Mode

JPEG XL lossless

Additional Information (Optional)

No response

[novaexe]

https://exiftool.org/forum/index.php?topic=16491.0

It has to be custom implanted into exiftool as it's not a standard meta tag