Steps
Create a new monomer and give it the same symbol as an existing one.
Save the monomer.
On saving the existing one is overwritten so it does not create a duplicate. (creating a duplicate would be bad). It would be better if it warned you first and refused to save at all.
Steps Create a new monomer and give it the same symbol as an existing one. Save the monomer. On saving the existing one is overwritten so it does not create a duplicate. (creating a duplicate would be bad). It would be better if it warned you first and refused to save at all.