I would like request that images in signatures be disabled on enwiki. I believe
this reflects consensus at the provided URL. We would like this implemented
technically instead of as a guideline or policy because it avoids headaches; it
has long been a guideline not to use images in signatures, yet people still use
them and are sometimes quite stubborn when asked to remove them.
If this is not a $wg variable, perhaps it should be... I can put in the
appropriate feature request if necessary.