Steps to replicate the issue :
Import English articles that contains citations such as {{cite book}} {{cite journal}} {{cite web}} etc.. Or create an article and write a citation for example :
{{cite book |title = Sample Book}}
What happens?:
A lua error is generated :
Lua error in Module:Citation/CS1/Configuration at line 2058: attempt to index field '?' (a nil value).
What should have happened instead?:
Instead it should display the citation as follow :
Sample Book.
Software version:
Tested on mediawiki v1.41 and v1.42.0-wmf.23 same issue on both versions
Other information:
we've been using mediawiki for like 6 months there was no issue, it happened lately in the past month.
Browser: Google Chrome
Additional error details:
I will appreciate any guidance to help identify the problem and solve it.