Mozilla Thunderbird is a standalone mail and newsgroup client. This update upgrades Thunderbird to version 78.13.0. Security Fix(es): * Mozilla: Uninitialized memory in a canvas object could have led to memory corruption (CVE-2021-29980) * Mozilla: Incorrect instruction reordering during JIT optimization (CVE-2021-29984) * Mozilla: Race condition when resolving DNS names could have led to memory corruption (CVE-2021-29986) * Mozilla: Memory corruption as a result of incorrect style treatment (CVE-2021-29988) * Mozilla: Memory safety bugs fixed in Thunderbird 78.13 (CVE-2021-29989) * Mozilla: Use-after-free media channels (CVE-2021-29985) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.