Works against Firefox 65.0 on windows 64bit. CVE-2019-11708 part is taken from exploit by 0vercl0k:
https://github.com/0vercl0k/CVE-2019-11708
The exploit uses CVE-2019-9791 to obtain read/write primitive in content process then CVE-2019-11708 to make the main process load arbitrary url. In parent process CVE-2019-9791 is used again to obtain arbitrary code execution.