quote:
# Avatars & Signatures:
* Maximum avatar width: 150 pixels.
* Maximum signature dimensions: 590 pixels wide, 125 pixels high.
* Maximum file size for avatar images and total signature images: 100 kilobytes.
* Images must work, and must load reasonably fast.
That's the only rules for avatars and signatures. So advertising is fine in signatures, but like Nathan said, if it's over the top, then it may get removed.
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