Steps to reproduce the issue

1. Start on a site where Jetpack and its comment Likes modules are active.
2. Switch the site language to French.
3. Note that the strings for Comment Likes are translated into French:
   https://translate.wordpress.com/projects/wpcom/fr/default/?filters%5Bterm%5D=Liked+by&filters%5Buser_login%5D=&filters%5Bstatus%5D=current_or_waiting_or_fuzzy_or_untranslated&filters%5Bview%5D=&filter=Filter&sort%5Bby%5D=priority&sort%5Bhow%5D=desc
4. While the translation appears properly when a comment hasn't been liked yet, it is not correct for comments that have been liked at least once:

Reported in 693464-zen