We have those 2 colors in the palette of the png:
0x00F0F0 and 0x00F0F1
Once displayed in 4444 on a 16 bpp display, both color
will be 0x0FF. (565 could also be supported of course)
So 0x00F0F1 could be removed from the palette and all
pixels pointing to this color should be re-indexed to
point to 0x00F0F0.
Feasable? I hope so...