In the security bug fixes: >>> CVE-2020-12387: Use-after-free during worker shutdown >>> Impact: critical >>> A race condition when running shutdown code for

In the security bug fixes: >>> CVE-2020-12387: Use-after-free during worker shutdown >>> Impact: critical >>> A race condition when running shutdown code for Web Worker led to a use-after-free vulnerability. This resulted in a potentially exploitable crash. And: >>> CVE-2020-12388: Sandbox escape with improperly guarded Access Tokens >>> Impact: critical >>> The Firefox content processes did not sufficiently lockdown access control which could result in a sandbox escape. [On Windows] So a sandbox escape and a way to be in a position to need a sandbox escape.