Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability. This update upgrades Firefox to version 91.4.0 ESR. Security Fix(es): * Mozilla: Memory safety bugs fixed in Firefox 95 and Firefox ESR 91.4 * Mozilla: URL leakage when navigating while executing asynchronous function (CVE-2021-43536) * Mozilla: Heap buffer overflow when using structured clone (CVE-2021-43537) * Mozilla: Missing fullscreen and pointer lock notification when requesting both (CVE-2021-43538) * Mozilla: GC rooting failure when calling wasm instance methods (CVE-2021-43539) * Mozilla: External protocol handler parameters were unescaped (CVE-2021-43541) * Mozilla: XMLHttpRequest error codes could have leaked the existence of an external protocol handler (CVE-2021-43542) * Mozilla: Bypass of CSP sandbox directive when embedding (CVE-2021-43543) * Mozilla: Denial of Service when using the Location API in a loop (CVE-2021-43545) * Mozilla: Cursor spoofing could overlay user interface when native cursor is zoomed (CVE-2021-43546) 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.