Preview-Generator Bilder
The app does not replace on demand preview generation so if a preview is requested before it is pre-generated it will still be shown. The first time you install this app, before using a cron job, you properly want to generate all previews via: ./occ preview:generate-all -vvv
Important: To enable pre-generation of previews you must add php /var/www/nextcloud/occ preview:pre-generate to a system cron job that runs at times of your choosing.