[USN-3645-2] Firefox regression

USN-3645-1 fixed vulnerabilities in Firefox. The update caused an issue
where users experienced long UI pauses in some circumsances. 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 in to opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service via application
crash, bypass same-origin restrictions, conduct cross-site scripting (XSS)
attacks, install lightweight themes without user interaction, spoof the
filename in the downloads panel, or execute arbitrary code.
(CVE-2018-5150, CVE-2018-5151, CVE-2018-5153, CVE-2018-5154,
CVE-2018-5155, CVE-2018-5157, CVE-2018-5158, CVE-2018-5159, CVE-2018-5160,
CVE-2018-5163, CVE-2018-5164, CVE-2018-5168, CVE-2018-5173, CVE-2018-5175,
CVE-2018-5177, CVE-2018-5180)

Multiple security issues were discovered with WebExtensions. If a user
were tricked in to installing a specially crafted extension, an attacker
could potentially exploit these to obtain sensitive information, or bypass
security restrictions. (CVE-2018-5152, CVE-2018-5166)

It was discovered that the web console and JavaScript debugger incorrectly
linkified chrome: and javascript URLs. If a user were tricked in to
clicking a specially crafted link, an attacker could potentially exploit
this to conduct cross-site scripting (XSS) attacks. (CVE-2018-5167)

It was discovered that dragging and dropping link text on to the home
button could set the home page to include chrome pages. If a user were
tricked in to dragging and dropping a specially crafted link on to the
home button, an attacker could potentially exploit this bypass security
restrictions. (CVE-2018-5169)

It was discovered that the Live Bookmarks page and PDF viewer would run
script pasted from the clipboard. If a user were tricked in to copying and
pasting specially crafted text, an attacker could potentially exploit this
to conduct cross-site scripting (XSS) attacks. (CVE-2018-5172)

It was discovered that the JSON viewer incorrectly linkified javascript:
URLs. If a user were tricked in to clicking on a specially crafted link,
an attacker could potentially exploit this to obtain sensitive
information. (CVE-2018-5176)

It was discovered that dragging a file: URL on to a tab that is running in
a different process would cause the file to open in that process. If a
user were tricked in to dragging a file: URL, an attacker could
potentially exploit this to bypass intended security policies.
(CVE-2018-5181)

It was discovered that dragging text that is a file: URL on to the
addressbar would open the specified file. If a user were tricked in to
dragging specially crafted text on to the addressbar, an attacker could
potentially exploit this to bypass intended security policies.
(CVE-2018-5182)