Red spots showing up during upscale

[virox]

Hey, thanks for creating this extension!

Today, I've discovered a bug with one of my images I tried to upscale. For testing, you can find it attached below.
The input resolution is 1920x2880px, and I'm simply trying to upscale it by a factor of 2. For some reason, especially in the blurry background, red/bright sports appear during the denoise process (they can be seen in the preview during the generation). After the upscale is finished, they are still visible.

Here are the settings I used (no prompt given):
Steps: 35, Sampler: DPM++ SDE Karras, CFG scale: 7, Seed: 802614410, Size: 3840x5760, Model hash: 61e23e57ea, Model: mixProV4_v4, VAE: clearvae_main, Denoising strength: 0.35, Clip skip: 2, Version: v1.2.1, Ultimate SD upscale upscaler: 4x-UltraSharp, Ultimate SD upscale tile_width: 512, Ultimate SD upscale tile_height: 512, Ultimate SD upscale mask_blur: 8, Ultimate SD upscale padding: 32

Is this something that can be fixed in your script, or is this an issue with Stable Diffusion itself?

This is the first tile of the original image:

This is the preview image during the redrawing of the first tile:

This is the finished first tile:

This is the original image used:

[Jopezzia]

This is generation color problem. Try to use https://github.com/klimaleksus/stable-diffusion-webui-anti-burn for fix this