Support Gem duplication

I unwantedly duplicated a support gem, no idea how, but i'm 100% certain i duplicated it.

Inventory with only 5 maps, 40 wisdom scrolls and my aleady removed Muster support gem.

While using a lvl5 uncut support from stash and choosing my Tamed Beast gem, i notice that there's 4 supports already in (all 4 sockets available filled) and there was another muster socketed on my Tamed beast Gem. Removable, both are in my stash, and both are socketable again and work.

before socketing both, one had "+5 Int (55)" as requirement while the other had "+5 Int (50)". both are "+5 Int (50)" after socketing the 55 one.

I don't know what else i can add to this information.

This was absolutely unnitentionnal, just trying to test differents supports on skills.