I've noticed that any PNG on the site (user uploaded) is being desaturated and colors ruined.
To test, if you upload a PNG team logo, see the results and how the colors change / look desaturated (lack color). If you upload a JPG image, the colors are maintained and normal (vibrant as expected).
This also affects the livery generator because once the livery is saved, the resulting image you see on the Team page is a PNG, and thus your livery looks very different from the colors you had when in the Livery Designer.
Small bug, hopefully not intentional changes with the image compression software you're using :)
