Hires. Fix button from gallery not working

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Whenever I'm trying to use the Hires. Fix/upscale button from the gallery in txt2img after generating a batch, I'm getting a RuntimeError and the gallery is cleared. Hires. Fix as part of generating works though.
I'm using Animagine XL 4.0 Opt, an SDXL model.

Logs:
Traceback (most recent call last):
File "C:\SD\Forge\webui\modules_forge\main_thread.py", line 30, in work
self.result = self.func(*self.args, **self.kwargs)
File "C:\SD\Forge\webui\modules\txt2img.py", line 101, in txt2img_upscale_function
processed = processing.process_images(p)
File "C:\SD\Forge\webui\modules\processing.py", line 842, in process_images
res = process_images_inner(p)
File "C:\SD\Forge\webui\modules\processing.py", line 990, in process_images_inner
samples_ddim = p.sample(conditioning=p.c, unconditional_conditioning=p.uc, seeds=p.seeds, subseeds=p.subseeds, subseed_strength=p.subseed_strength, prompts=p.prompts)
File "C:\SD\Forge\webui\modules\processing.py", line 1364, in sample
samples = images_tensor_to_samples(image, approximation_indexes.get(opts.sd_vae_encode_method), self.sd_model)
File "C:\SD\Forge\webui\modules\sd_samplers_common.py", line 115, in images_tensor_to_samples
x_latent = model.get_first_stage_encoding(model.encode_first_stage(image))
File "C:\SD\Forge\system\python\lib\site-packages\torch\utils\_contextlib.py", line 115, in decorate_context
return func(*args, **kwargs)
File "C:\SD\Forge\webui\backend\diffusion_engine\sdxl.py", line 130, in encode_first_stage
sample = self.forge_objects.vae.encode(x.movedim(1, -1) * 0.5 + 0.5)
File "C:\SD\Forge\webui\backend\patcher\vae.py", line 189, in encode
return self.encode_inner(pixel_samples)
File "C:\SD\Forge\webui\backend\patcher\vae.py", line 178, in encode_inner
samples[x:x + batch_number] = self.first_stage_model.encode(pixels_in, regulation).to(self.output_device).float()
File "C:\SD\Forge\webui\backend\nn\vae.py", line 294, in encode
z = self.encoder(x)
File "C:\SD\Forge\system\python\lib\site-packages\torch\nn\modules\module.py", line 1532, in _wrapped_call_impl
return self._call_impl(*args, **kwargs)
File "C:\SD\Forge\system\python\lib\site-packages\torch\nn\modules\module.py", line 1541, in _call_impl
return forward_call(*args, **kwargs)
File "C:\SD\Forge\webui\backend\nn\vae.py", line 184, in forward
h = self.conv_in(x)
File "C:\SD\Forge\system\python\lib\site-packages\torch\nn\modules\module.py", line 1532, in _wrapped_call_impl
return self._call_impl(*args, **kwargs)
File "C:\SD\Forge\system\python\lib\site-packages\torch\nn\modules\module.py", line 1541, in _call_impl
return forward_call(*args, **kwargs)
File "C:\SD\Forge\webui\backend\operations.py", line 170, in forward
return super()._conv_forward(x, weight, bias)
File "C:\SD\Forge\system\python\lib\site-packages\torch\nn\modules\conv.py", line 456, in _conv_forward
return F.conv2d(input, weight, bias, self.stride,
RuntimeError: Given groups=1, weight of size [128, 3, 3, 3], expected input[1, 4, 768, 1344] to have 3 channels, but got 4 channels instead
Given groups=1, weight of size [128, 3, 3, 3], expected input[1, 4, 768, 1344] to have 3 channels, but got 4 channels instead

Reproduce the failure by using Hires. Fix from the txt2img gallery after generating a batch, then start at modules/txt2img.py and follow processing.py into sd_samplers_common.py, backend/diffusion_engine/sdxl.py, backend/patcher/vae.py, and backend/nn/vae.py. Check where the four-channel input reaches the three-channel VAE encoder. Done means gallery Hires. Fix works without the RuntimeError or clearing the gallery.

Written by the indexing model from the issue text.