Missing import/export functionality (present in older versions!)! Copying and pasting rules exported from older version into text-box areas is counter-intuitive (some of elements like prefixes and suffixes must be manually removed!)! A separate text-box area for "Element Hiding Rules" is missing (it is joined/merged with "Custom Filter Rules" now).
It lets through far too many advertisements and "Adblock Warning and blocking" screens (even with "Adblock Warning Removal List" and "ABP filters" added and enabled) - so it doesn't really do what it is supposed to do!
Shame on you, Adblock Plus!
I have abandoned you after many years together in favour of your rival uBlock Origin - their add-on is far more useful.