RFP ESR version spoof info

The last one-off ESR cycle of 8 releases is now behind us, new algorithm for FF60+ is back to 7 releases per ESR numbering, starting at 60... 67... etc. Note: This does not do anything for Aurora or Nightly spoofing the next ESR early (but we have until Nightly 67 before this becomes a problem). The ticket 1418162 was meant to cover this but instead was just used for the new algorithm. There is currently no ticket for the Aurora/Nightly issue - but never fear, Pants is here!! It is not forgotten, and I have emails with Tom Ritter et al on it

user.js

@@ -1566,7 +1566,7 @@ user_pref("privacy.firstparty.isolate.restrict_opener_access", true);
  ** 1369303 - spoof/disable performance API (see 2410-deprecated, 4602, 4603) (FF56+)
  ** 1333651 & 1383495 & 1396468 - spoof Navigator API (see section 4700) (FF56+)
       FF56: The version number will be rounded down to the nearest multiple of 10
-      FF57: The version number will match current ESR (1393283, 1418672)
+      FF57: The version number will match current ESR (1393283, 1418672, 1418162)
       FF59: The OS will be reported as Windows, OSX, Android, or Linux (to reduce breakage) (1404608)
  ** 1369319 - disable device sensor API (see 4604) (FF56+)
  ** 1369357 - disable site specific zoom (see 4605) (FF56+)