[Bug]: KeyError:'.' when I try to use outpanting (mk2 or poorman)

[hitrpr]

Is there an existing issue for this?

• I have searched the existing issues and checked the recent builds/commits

What happened?

Symphtoms looks similar to #5603
When i try to outpaint image, it can`t be saved after processing.
When status reaches 100% blurry image dissappear and i have an error in console.

Steps to reproduce the problem

img2img tab, input image, select outpaint script (mk2 for example), press Generate.

What should have happened?

Img start to process, but at the end it disappead and error appears,
it looks like python do not see any registred extensions and can`t save image

Commit where the problem happens

checkpoint: 52c8653a97

What platforms do you use to access the UI ?

Windows

What browsers do you use to access the UI ?

Mozilla Firefox, Google Chrome

Command Line Arguments

--xformers

List of extensions

multidiffusion-upscaler-for-automatic1111
posex
sd-webui-controlnet
stable-diffusion-webui-composable-lora
stable-diffusion-webui-two-shot

Console logs

Traceback (most recent call last):
  File "C:\SD\stable-diffusion-webui\modules\call_queue.py", line 56, in f
    res = list(func(*args, **kwargs))
  File "C:\SD\stable-diffusion-webui\modules\call_queue.py", line 37, in f
    res = func(*args, **kwargs)
  File "C:\SD\stable-diffusion-webui\modules\img2img.py", line 170, in img2img
    processed = modules.scripts.scripts_img2img.run(p, *args)
  File "C:\SD\stable-diffusion-webui\modules\scripts.py", line 407, in run
    processed = script.run(p, *script_args)
  File "C:\SD\stable-diffusion-webui\scripts\poor_mans_outpainting.py", line 141, in run
    images.save_image(combined_image, p.outpath_samples, "", initial_seed, p.prompt, opts.grid_format, info=initial_info, p=p)
  File "C:\SD\stable-diffusion-webui\modules\images.py", line 584, in save_image
    _atomically_save_image(image, fullfn_without_extension, extension)
  File "C:\SD\stable-diffusion-webui\modules\images.py", line 546, in _atomically_save_image
    image_format = Image.registered_extensions()[extension]
KeyError: '.'

Additional information

No response

[wywywywy]

Show us the options you've set in the Saving Images setting tab?

[hitrpr]

default settings, i suppose

[wywywywy]

Try to put png into the "File format for grids", apply the settings, and try again.

[hitrpr]

yep, suddenly it works, despite weird! Thanks

I am not sure it should depend on grid extension, when there is no grid generation (single image processing)
Also grids generated in other modes properly and as far as i see, there are .png default inside scripts for cases with missed extension

[wywywywy]

Thanks very much for the report.

It appears that there's a bug where it's mistakenly using the Grid file format rather than the Sample file format. And the bug was probably introduced by me 😔 My apologies.

[hitrpr]

Oh, I see. So i will leave it opened until fix. Thanks for help again

[wywywywy]

PR #9258 submitted