Installation in a FreeNAS-11.3-U3.2 jail - internal server error

Hi everyone,
I’m new to the forum and relatively new to nextcloud. Until now I did 4-5 installations to test things, one of them manually on debian VM system from scratch. Since FreeNAS is a freebsd based I followed this excellent guide.
I had success till the setup screen of nextcloud where we put a user, a data folder etc.
After populating the info, which by the way is the same as in the guide, I get an internal server error like this:

Internal Server Error

The server encountered an internal error and was unable to complete your request.
Please contact the server administrator if this error reappears multiple times, please include the technical details below in your report.
More details can be found in the server log.

In /var/log/nextcloud/nextcloud.log I get a message like this:

{“reqId”:”BkHMptdWyx7Xdg4oICdN”,”level”:3,”time”:”2020-06-15T06:50:37+00:00″,”remoteAddr”:”192.168.120.1″,”user”:”–“,”app”:”core”,”method”:”GET”,”url”:”/index.php/login”,”message”:{“Exception”:”RuntimeException”,”Message”:”Could not get appdata folder for js”,”Code”:0,”Trace”:[{“file”:”/usr/local/www/nextcloud/lib/private/Files/AppData/AppData.php”,”line”:157,”function”:”getAppDataFolder”,”class”:”OC\Files\AppData\AppData”,”type”:”->”},{“file”:”/usr/local/www/nextcloud/lib/private/Template/JSCombiner.php”,”line”:100,”function”:”newFolder”,”class”:”OC\Files\AppData\AppData”,”type”:”->”},{“file”:”/usr/local/www/nextcloud/lib/private/Template/JSResourceLocator.php”,”line”:116,”function”:”process”,”class”:”OC\Template\JSCombiner”,”type”:”->”},{“file”:”/usr/local/www/nextcloud/lib/private/Template/JSResourceLocator.php”,”line”:72,”function”:”cacheAndAppendCombineJsonIfExist”,”class”:”OC\Template\JSResourceLocator”,”type”:”->”},{“file”:”/usr/local/www/nextcloud/lib/private/Template/ResourceLocator.php”,”line”:79,”function”:”doFind”,”class”:”OC\Template\JSResourceLocator”,”type”:”->”},{“file”:”/usr/local/www/nextcloud/lib/private/TemplateLayout.php”,”line”:344,”function”:”find”,”class”:”OC\Template\ResourceLocator”,”type”:”->”},{“file”:”/usr/local/www/nextcloud/lib/private/TemplateLayout.php”,”line”:173,”function”:”findJavascriptFiles”,”class”:”OC\TemplateLayout”,”type”:”::”},{“file”:”/usr/local/www/nextcloud/lib/private/legacy/OC_Template.php”,”line”:185,”function”:”__construct”,”class”:”OC\TemplateLayout”,”type”:”->”},{“file”:”/usr/local/www/nextcloud/lib/private/Template/Base.php”,”line”:132,”function”:”fetchPage”,”class”:”OC_Template”,”type”:”->”},{“file”:”/usr/local/www/nextcloud/lib/private/legacy/OC_Template.php”,”line”:334,”function”:”printPage”,”class”:”OC\Template\Base”,”type”:”->”},{“file”:”/usr/local/www/nextcloud/index.php”,”line”:63,”function”:”printExceptionErrorPage”,”class”:”OC_Template”,”type”:”::”}],”File”:”/usr/local/www/nextcloud/lib/private/Files/AppData/AppData.php”,”Line”:118,”CustomMessage”:”–“},”userAgent”:”Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:77.0) Gecko/20100101 Firefox/77.0″,”version”:”19.0.0.12″}

In apache’s http-access.log I get this:

[15/Jun/2020:08:51:26 +0200] “GET /index.php/login HTTP/1.1” 500 289

Now in the nextcloud.log this line brings my attention:

Could not get appdata folder for js…

I made sure my permissions in the nextcloud folder are 750 for the folders and 640 for the files. I also checked the ownership of the files and folders to be www for user and www for the group.
Does anyone have an idea what could be wrong?

P.S. During installation of php, mariadb and apache I chose the latest versions available.
PHP 7.4.6
mariadb104-server-10.4.13_2
apache24-2.4.43
redis-5.0.9

PHP modules:
apcu
bz2
Core
ctype
curl
date
dom
exif
fileinfo
filter
gd
hash
iconv
intl
json
ldap
libxml
mbstring
mysqlnd
openssl
pcre
PDO
pdo_mysql
posix
redis
Reflection
session
SimpleXML
SPL
standard
xml
xmlreader
xmlwriter
xsl
Zend OPcache
zip
zlib

Can you check for the http-error log?