CVE-2020-26960
If the Compact() method was called on an nsTArray, the array could have been reallocated without updating other pointers, leading to a potential use-after-free and exploitable crash. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5. Date published : 2020-12-08 https://www.mozilla.org/security/advisories/mfsa2020-50/