idbeholdME: Downscaling usually brings the quality so low I don't bother uploading it. I now just stick with crops and compression and hope for the best, but pretty often, it's not enough. All depends on how much I can crop.
DrazenCro: I remember you from "Take and post a screenshot...." topic.
Especially when you said "Where are we, stone age?"
https://www.gog.com/forum/general/take_and_post_a_screenshot_of_what_youre_playing_right_now/post3452 Not sure why gog can't add some option that when user upload one image he could upload it up to 2 mb size, but no, having current limit is so cool.
Those 2 mb would be enough for those who upload 4k images, it would be managable to bring it to that size. But having current limit it is really hard, you just need to resize the 4k image, but that is not the way it is suppose to work.
Anyway, for me faststone image viewer works perfectly fine since I am on resolution that doesn't need resizing or sth, I just add some colors to it i.e. a little change in brightness, contrast, saturation and also with it I can see the final save size.
Here is also an example that some 4k image can kinda look good if you resize it, in some way especially if you play with colors a little bit, it looks good on my side but that is maybe because image will fit to my smallish browser size. Everyone up for its taste.
4k
https://images.hdqwalls.com/wallpapers/doom-eternal-4k-2020-75.jpg 2048x1152 - size just enough for gog limit
https://www.gog.com/upload/forum/2020/08/a01cec19f6085bf77e92ed2f36d26535b0da7a79.jpg Kinda fun... watching it get smaller and smaller, though of course 4k is harder to compress down without things starting to get a bit weird.