We discovered an issue with blood transfusions.

If the recipient is treated with their own blood type,

A+ to A+
A- to A-
B+ to B+
B- to B-
AB+ to AB+
AB- to AB-
0+ to 0+
0- to 0-

everything works as expected. The recipient immediately restores the blood amount which the blood bag contains.

If the recipient is treated with the universal blood type (0-),

0- to A+
0- to A-
0- to B+
0- to B-
0- to AB+
0- to AB-
0- to 0+

the recipient won't restore any blood, no faster blood regeneration, nothing happens.

I don't think this is intended, if I know right this worked in earlier versions just like treating someone with their own blood type.