I am running my nextcloud on a local box with a docker-based installation (apache-image from the docker-examples), it is updated to nextcloud 18.
When trying to install the document server i get the following error:
cURL error 28: Operation timed out after 30000 milliseconds with 71258684 out of 305969549 bytes received (see http://curl.haxx.se/libcurl/c/libcurl-errors.html)
I do have internet connection and the error indicates, that only ~40% of some download worked, too.
This happens through the normal app-store installation and nothing more.
docker-compose logs -f does not give any more insights.