I did read it and don't see solution
By the way just because of this problem I have purchased Photoshop
and guess what? Photoshop has 300k pixel dimension limitation
So I had to split images into half dimension. I used pil library and then Photoshop was able to open them
After that I edited in Photoshop and saved. So photoshop was able to open edit and save 254418 x 4188 pixels image
Then I used Python again to merge into full image
So Paint .net and gimp was able to open images. However I wasn't able to save on those 2.
Photoshop wasn't able to open full image but it was able to edit and save 254k x 4k resolution
I am doing all on Windows 10