Sioner's temper does cannot be placed into Skelleton Frost Mage anymore

Title says it. I didn't used my Skelleton Frost Mage minions for some time and now i wanted again and observed that thesupport gem Sioner's temper does not go into a slot there anymore which it previously did and should.

Interesting is also that if i insert Multishot and then try to insert Sioners, the tooltip says i already have such a gem placed (the multishot).

So last update or so must have broken this.