Steps to reproduce
Fresh owncloud install on ubuntu 18.04
Connecting to the web server for the first time I expected to see the initial setup page
List of missing PHP modules including zip, dom, xmlWriter, xmlReader, mb multibyte, curl, intl etc.
ownCloud version: (see ownCloud admin page)
Updated from an older ownCloud or fresh install:
Was surprised how little information there was around to fix these issues. Particularly for mb multibyte.
the following steps will resolve these:
apt install php-zip
apt install php-xm # Includes dom and several others
apt install php-intl
apt install curl php-curl
apt install php-mbstring
systemctl reload apache2
Reload the browser web page and you should get the initial setup page.