Support gem "Life Thief" doesn't do anything

It doesn't seem to be leeching life.
Short video to demonstrate:

https://streamable.com/ygu9wc

On average hitting for 1000 mostly physical damage.
6% life leech on the gem.

Reading leech's description it says enemies gain a resistance to it scaled by level. In the video I attack white mobs in a zone level ~45. So even if they have say 50% leech resistance, I should still be seeing at least 30 life returned per hit over 1 second. I'm seeing absolutely no change in the life regen when I hit anything. The only time it changes is when I move, but that's because of a life regeneration while moving passive node.

I believe all life leech (probably mana leech too) is bugged.

Blood mage is completely terrible right now, it's only making my character worse so I spent 30k gold to unspec, basically my entire wealth.

Waiting until this is patched to respec back in.

NEEDS ATTENTION ASAP with a hotfix, not wait for a full patch later this week or next week. It's breaking the class completely.