institution mapping does not work and geoinformation for institutions missing
Some time ago we implemented geoinformations for institutions in the search index - see #126 (closed)
Currently there are much less records with geoinformation data than there were last year - at least for Germany. See also https://tibhannover.gitlab.io/oer/oer-statistic-page/map.html
We should check why there is less geolocation data and fix any problem we find.