Many warnings from libpng

[ghostbuster]

When playing on windows, and running the game form a (cygwin) terminal, the game generates **hundreds** of warning from libpng:
libpng warning: iCCP: known incorrect sRGB profile

No information written in the log, only on the console. It happens even in the welcome screen.

No impact on the game itself, but it is obviously erronous.

[ghostbuster]

Now the situation is worse.

Not only my console is permanently spammed with messages about the sRGB profile, but there are crashes.
I get several times the following message:

libpng warning: Interlace handling should be turned on when using the png_read_image

And the program just exits.
This happened a couple of times.
No message in the te4_log.