Since 4 or 5 days, Google Search Console send me some errors : data-vocabulary.org schema deprecated
According to Google, it comes from Vanilla forum.
We have until 6 april 2020 to correct it, so I suppose the future update will solve the problem?
Yes, I have seen this too and it is not trivial as it affects the Path/Breadcrumbs information in Googles search results.
Guidelines are: https://schema.org/ListItem
There are some fixes that need to be applied to ~/library/core/class.theme.php or JSON-ld.
It seems its gonna get fixed in future releases: https://github.com/vanilla/vanilla/issues/3116