Log Message:
firefox78: Update to 78.13.0

Changelog:
Various stability, functionality, and security fixes

Security fixes:
#CVE-2021-29986: Race condition when resolving DNS names could have led to
 memory corruption
#CVE-2021-29988: Memory corruption as a result of incorrect style treatment
#CVE-2021-29984: Incorrect instruction reordering during JIT optimization
#CVE-2021-29980: Uninitialized memory in a canvas object could have led to
 memory corruption
#CVE-2021-29985: Use-after-free media channels
#CVE-2021-29989: Memory safety bugs fixed in Firefox 91 and Firefox ESR 78.13