FVD SpeedDial started to behave arbitrarily and seems to open up pages that it is currently refreshing in the background of the browser (Firefox). The page even pops up in Mac OS Firefox for a few seconds, which makes SpeedDial unable to be used as it takes over the control. When you click the Firefox icon from the Mac Dock/Win Task Manager, you will see that each time a new browser tab opens in the background. This issue would need an immediate fix.
I find the currant Speed Dial tab organisation very irritating.
If you can roll back this is the fix in fire fox to force multi threading, and FVD speed dial worked great, this new one is awful.
follow these instructions
If you're using Firefox 48 or later, you might be using e10s already. Check about:support and look for a number higher than 0 in the "Multiprocess Windows" entry. If you would like to opt-in, open about:config and toggle browser.tabs.remote.autostart to true. On your next restart, e10s should be active.
If you've tried enabling e10s following the instruction above, but your about:support indicates that e10s is disabled (e.g., accessibility, add-ons can trigger this), you can force e10s on for testing purposes. Within about:config create a new boolean pref named browser.tabs.remote.force-enable and set it to true. This is not encouraged, use it at your own risk!
Link to Wiki https://wiki.mozilla.org/Electrolysis
Customer support service by UserEcho