I was not sure if this belonged under Firefox or Android sub Forum topics.
I have 2 tablets running Firefox Beta 52.0b2
1 - Samsung Galaxy Tab A running CyanogenMod Android 4.2.2
2 - Samsung Galaxy Tab E running Android 6.0.1
both have the same problem.
Many ads are displayed on all sites (mostly Taboola ?).
When I go to Tools - Add-ons - AdBlock Plus (v2.8.2) and touch to go to Settings, the resulting page is Blank.
There are no options listed, No Lists available, No Check boxes. Only choices are Disable and Uninstall.
Uninstalled, reinstalled, cleared Firefox and still no Options available.
On same tablets, Firefox Normal (50.1.0) AdBlock Plus works well and Options are all listed.