Thunderbird links redirect to Dropbox

I recently used the update script to install the latest version of Netrunner from the previous version. Since then, clicking any link in an email in Thunderbird sends Firefox to

Considering both my Thunderbird and Firefox packages came directly from the Netrunner repositories, I’m a little concerned. Any advice?

This sounds to me like a thunderbird issue.
Thunderbird however introduced sharing big files via e-mail by using dropbox and other services maybe it is related to this.
Try checking if the default webbrowser setting is set up correctly:

Thanks Leszek. That’s interesting - I didn’t know about a partnership between Mozilla and Dropbox. How disappointing.

I’ve used their support website to submit a ticket. In the meantime perhaps I’ll try reinstalling the package.