The following has been in the site rules/guidelines for a long time, but hasn't been actively enforced lately:
"Signatures should follow all the guidelines and rules that apply to posts. In addition, any reference to a user on this site should be removed immediately if that user asks you to."
With the move toward an "adult" vs. "family/work-friendly" split in discussion forums (SE and GD), I wanted to re-emphasize this rule regarding signatures. Your signature appears attached to every post you make, and will therefore be held to a higher standard. As a general rule of thumb, if you can't post it in GD, don't put it in your signature.
The same applies to avatars - additionally, it has always been the policy of this site to remove avatars which are particularly attention drawing (specifically rapidly-flashing animated avatars).
If you see a problem with a user's sig or avatar, please report it to me by PM.
Clarification/addendum based on moderator/administrator discussion: Blacklisting does not belong in signatures. We suggest creating a wiki blacklist or something similar so you can direct mods to that without cluttering every post.
In post 2, Soren wrote:Hi I see that no one uses images in their signatures, whereas that is the norm in many other forums.
May I ask why?
As long as it's small it should be fine right?
Image tags were removed from sigs because abuse. It's better to not risk someone putting in a NSFW image in their sig,however silly that may sound, because lots of us view from work.
"Animorpherv1's posts are so powerful that prolonged exposure may cause vertigo, nausea, acute tinnitus, and in rare cases, death." - vonflare
Is there a reason [font] tags are disabled in signatures? It's not a big deal or anything, but I tried to use them in a sig recently and noticed they were disabled.