Media Gallery Upload Thumbnail Compression is Changing Image Hue

That is a huge difference!

I think this is your issue…

Any time an image is uploaded, if that image was saved in the Adobe RGB color space, then the image does not get loaded correctly for resizing. Thumbnails are saved in the default color space, which is sRGB. By failing to perform the color conversion, and then failing to specify the non-default color space in EXIF, thumbnails are produced with colors that are noticeably different from the original.

Try converting your images to use sRGB, re-saving and re-uploading them.

Reference – https://graphpaperpress.com/tips/fix-image-color-saturation-loss-in-wordpress/

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