JPEG XL Support?

[LajamerrMittesdine]

Traceback (most recent call last):
  File "C:\Users\xxxxx\stable-diffusion-webui\venv\lib\site-packages\PIL\Image.py", line 2298, in save
    format = EXTENSION[ext]
KeyError: '.jxl'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "C:\Users\xxxxx\stable-diffusion-webui\modules\ui.py", line 187, in f
    res = list(func(*args, **kwargs))
  File "C:\Users\xxxxx\stable-diffusion-webui\webui.py", line 64, in f
    res = func(*args, **kwargs)
  File "C:\Users\xxxxx\stable-diffusion-webui\modules\txt2img.py", line 44, in txt2img
    processed = process_images(p)
  File "C:\Users\xxxxx\stable-diffusion-webui\modules\processing.py", line 466, in process_images
    images.save_image(image, p.outpath_samples, "", seeds[i], prompts[i], opts.samples_format, info=infotext(n, i), p=p)
  File "C:\Users\xxxxx\stable-diffusion-webui\modules\images.py", line 447, in save_image
    image.save(fullfn, quality=opts.jpeg_quality, pnginfo=pnginfo)
  File "C:\Users\xxxxx\stable-diffusion-webui\venv\lib\site-packages\PIL\Image.py", line 2300, in save
    raise ValueError(f"unknown file extension: {ext}") from e
ValueError: unknown file extension: .jxl

This is low priority for me but it would be nice to see support for JPEG XL/.jxl as an output option.

[LajamerrMittesdine]

Related to this issue was a recent commit ddf6899

However it's not full support as this error is still present.

Traceback (most recent call last):
  File "C:\Users\xxxxx\stable-diffusion-webui\venv\lib\site-packages\PIL\Image.py", line 2298, in save
    format = EXTENSION[ext]
KeyError: '.jxl'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "C:\Users\xxxxx\stable-diffusion-webui\modules\ui.py", line 215, in f
    res = list(func(*args, **kwargs))
  File "C:\Users\xxxxx\stable-diffusion-webui\webui.py", line 64, in f
    res = func(*args, **kwargs)
  File "C:\Users\xxxxx\stable-diffusion-webui\modules\txt2img.py", line 44, in txt2img
    processed = process_images(p)
  File "C:\Users\xxxxx\stable-diffusion-webui\modules\processing.py", line 466, in process_images
    images.save_image(image, p.outpath_samples, "", seeds[i], prompts[i], opts.samples_format, info=infotext(n, i), p=p)
  File "C:\Users\xxxxx\stable-diffusion-webui\modules\images.py", line 447, in save_image
    image.save(fullfn, quality=opts.jpeg_quality, pnginfo=pnginfo)
  File "C:\Users\xxxxx\stable-diffusion-webui\venv\lib\site-packages\PIL\Image.py", line 2300, in save
    raise ValueError(f"unknown file extension: {ext}") from e
ValueError: unknown file extension: .jxl

[seadra]

kohya recently added support for jxl using https://github.com/olokelo/jxlpy