  This paper presents a collection of highly comparable web corpora of
Slovenian, Croatian, Bosnian, Montenegrin, Serbian, Macedonian, and Bulgarian,
covering thereby the whole spectrum of official languages in the South Slavic
language space. The collection of these corpora comprises a total of 13 billion
tokens of texts from 26 million documents. The comparability of the corpora is
ensured by a comparable crawling setup and the usage of identical crawling and
post-processing technology. All the corpora were linguistically annotated with
the state-of-the-art CLASSLA-Stanza linguistic processing pipeline, and
enriched with document-level genre information via the Transformer-based
multilingual X-GENRE classifier, which further enhances comparability at the
level of linguistic annotation and metadata enrichment. The genre-focused
analysis of the resulting corpora shows a rather consistent distribution of
genres throughout the seven corpora, with variations in the most prominent
genre categories being well-explained by the economic strength of each language
community. A comparison of the distribution of genre categories across the
corpora indicates that web corpora from less developed countries primarily
consist of news articles. Conversely, web corpora from economically more
developed countries exhibit a smaller proportion of news content, with a
greater presence of promotional and opinionated texts.
