Sorry for the delay.
So, the link problem is with Thunderbird. I'll go check a few pref's and see what I can dig up.
A thought has occurred to me in light of your last post or two. I don't know if you know, but there is an extension for Thunderbird called
ThunderBrowse which allows you to open links within Thunderbird without opening your browser. Follow the link and check it out. I've been using it for a while and it's good.