- Mozilla Firefox 66.0
* Increased content processes to 8
* Added capability to search through open tabs from the tab overflow menu
* New backend for the storage.local WebExtensions API, providing
I/O performance improvements when the extension updates a small
subset of the stored data
* WebExtension keyboard shortcuts can now be managed or overridden
from about:addons
* Improved scrolling behavior: Firefox will now attempt to keep content
from jumping around while a page is loading by supporting scroll
anchoring
* New about:privatebrowsing with search
* A certificate error page now notifies the user of the name of the
certificate issuer that breaks HTTPs connections on intercepted
connections to help troubleshooting possible anti-virus software
issues.
* Fixed an performance issue some Linux users experienced with the
Downloads panel (bmo#1517101)
* Firefox now blocks all autoplay media with sound by default. Users
can add individual sites to an exceptions list or turn the blocking
off.
* System title bar is hidden by default to match Gnome guideline
MFSA 2019-07 (bsc#1129821)
* CVE-2019-9790 (bmo#1525145)
Use-after-free when removing in-use DOM elements
* CVE-2019-9791 (bmo#1530958)
Type inference is incorrect for constructors entered through on-stack
replacement with IonMonkey
* CVE-2019-9792 (bmo#1532599)
IonMonkey leaks JS_OPTIMIZED_OUT magic value to script