Updated thunderbird packages fix security vulnerabilities:
Covert Content Attack on S/MIME encryption using a crafted multipart/ alternative message (CVE-2019-11739).
Memory safety bugs fixed in Firefox 69, Firefox ESR 68.1, Firefox ESR 60.9, Thunderbird 68.1, and Thunderbird 60.9 (CVE-2019-11740)
Same-origin policy violation with SVG filters and canvas to steal cross-origin images (CVE-2019-11742)
Cross-origin access to unload event attributes (CVE-2019-11743)
XSS by breaking out of title and textarea elements using innerHTML (CVE-2019-11744)
Use-after-free while manipulating video (CVE-2019-11746)
Use-after-free while extracting a key value in IndexedDB (CVE-2019-11752)