I'm getting a message from PageSpeed Insights that recommends to compress some
png images. E.g:
If compressing .../logo.png without loosing information, you would save 1.014 B (12% redcuction).
However, I've compressed the image with "Save for web" option and with the maximum compression. Tried to compress more times, but the image is never compressed more than about 200B. I could compress with PNG-8, but then I'm loosing image quality.
All other formats seem to be well compressed by Gimp with the same option. Any idea of why it's happening and how to solve it?