Crossref export is missing prefix in title

Description of issue or problem I’m having:
CrossRef Export doesn’t include prefix in title.

Steps I took leading up to the issue:
I exported a publication which has a title and a prefix.

What I tried to resolve the issue:
Searched up online for people having the same issue and have a look at the crossref-plugin-code

Application Version - e.g., OJS 3.1.2:
OJS and

Is this by design? What would be the best practice to add the suffix in the exported xml?

Thanks for your inputs!

Made a Pullrequest for it: