according to e.g. Best way to combine/merge categories when importing topics?
I have moved several thousand topics to other categories. Some of the left-over-categories were even empty then and could not be deleted.
Now I could delete them by manually setting categories.topic_count to 0, since discouse says that categories that are non-empty can not be deleted because it did not refresh that value when I emptied the category by moving all topics to another.
Using the method mentioned in the link above, the counts are not being updated nevertheless.
Somewhere I read to
wait until some job does that. Is this true?
If so, how can one issue that job manually?