I found this bug during computer analysis.
I had 4 Queens. Each at c4, c6, e4 and e6.
Moving either queen on c file to d5 file shows Qcd5 and moving either queen from 4th rank shows Q4d5.
Both times it is incorrect.
It should be Qc4d5, Qc6d5, Qe4d5 and Qe6d5.