USN-6509-2: Firefox regressions

USN-6509-1 fixed vulnerabilities in Firefox. The update introduced
several minor regressions. This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

Multiple security issues were discovered in Firefox. If a user were
tricked into opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service, obtain sensitive
information across domains, or execute arbitrary code. (CVE-2023-6206,
CVE-2023-6210, CVE-2023-6211, CVE-2023-6212, CVE-2023-6213)

It was discovered that Firefox did not properly manage memory when
images were created on the canvas element. An attacker could potentially
exploit this issue to obtain sensitive information. (CVE-2023-6204)

It discovered that Firefox incorrectly handled certain memory when using a
MessagePort. An attacker could potentially exploit this issue to cause a
denial of service. (CVE-2023-6205)

It discovered that Firefox incorrectly did not properly manage ownership
in ReadableByteStreams. An attacker could potentially exploit this issue
to cause a denial of service. (CVE-2023-6207)

It discovered that Firefox incorrectly did not properly manage copy
operations when using Selection API in X11. An attacker could potentially
exploit this issue to obtain sensitive information. (CVE-2023-6208)

Rachmat Abdul Rokhim discovered incorrectly handled parsing of relative
URLS starting with "///". An attacker could potentially exploit this issue
to cause a denial of service. (CVE-2023-6209)