I'm afraid the max size is even lower than that: 73.2kb
.png files lets you have transparency ... but they are not necessarily always "larger". That is, depending on what kind of .png file you'll be saving your sig into.
Images are automatically saved as PNG-24 (the one which has high image quality and size -- the one you must me pertaining to), which is big and will of course be rejected when you try to upload it. However, some editing programs let you select PNG-8, resulting in a smaller file size, even smaller than that of a .gif file.
The quality is not as great as that of a PNG-24, but it looks good nonetheless, dithered or not. I'm using that file type more often now, since PNG-8s look just the same as a .gif output for less kb![]()
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