@Fifty @hgtonight provided a fix for this here: http://vanillaforums.org/discussion/30967/vanilla-2-1-12-update-css-issues#latest which solves the issue for any images affected.
Also having an avatar issue. I posted a new thread here: http://vanillaforums.org/discussion/30967/vanilla-2-1-12-update-css-issues#latest @hgtonight fixed it for me.