I just started using Thunderbird. I think this is signature related. I struggled creating a nice signature. It seemed to work at first but by my second attempt the image never showed up in my drafts, only a square where it should be. Trying to send test emails with the empty box started this "attaching" sequence that never stops until I physically delete the empty image box. Then the emails send. So I created a html signature with no image. Still trying to attach. Then I unchecked all signature options and still it is trying to attach something. What is it?