Merging authors can lose alternate name links. For example, if you merge "Canon1", which has "Alternate1" as an alternate name, with "Canon2", which has "Alternate2" as it alternate name", the resulting merged canonical name will have "Alternate1" -- but not "Alternate2" -- as an alternate name.
Anonymous
Fixed in mod/aa_merge.py, installed in SVN 824 on 2022-01-03. Closing the Bug report.