  What types of governance arrangements makes some self-governed online groups
more vulnerable to disinformation campaigns? To answer this question, we
present a qualitative comparative analysis of the Croatian and Serbian
Wikipedia editions. We do so because between at least 2011 and 2020, the
Croatian language version of Wikipedia was taken over by a small group of
administrators who introduced far-right bias and outright disinformation;
dissenting editorial voices were reverted, banned, and blocked. Although
Serbian Wikipedia is roughly similar in size and age, shares many linguistic
and cultural features, and faced similar threats, it seems to have largely
avoided this fate. Based on a grounded theory analysis of interviews with
members of both communities and others in cross-functional platform-level
roles, we propose that the convergence of three features -- high perceived
value as a target, limited early bureaucratic openness, and a preference for
personalistic, informal forms of organization over formal ones -- produced a
window of opportunity for governance capture on Croatian Wikipedia. Our
findings illustrate that online community governing infrastructures can play a
crucial role in systematic disinformation campaigns and other influence
operations.
