Mozilla has fixed two security issues in this update.
Previous Thunderbird versions did not percent-encode spaces and double-quotes in URIs handed off to external programs for handling, which can cause the receiving program to mistakenly interpret a single URI as multiple arguments. This bug is fixed in Thunderbird 18.104.22.168.
Privilege escalation through chrome-loaded about:blank windows issue also has been fixed in Thunderbird 22.214.171.124.
Download Thunderbird 126.96.36.199