I tried to run “php flarum info” again, this time only relevant information, no errors.
# php flarum info
Flarum core 1.1.1
PHP version: 8.0.12
MySQL version: 5.6.50-log
Loaded extensions: Core, date, libxml, openssl, pcre, sqlite3, zlib, bcmath, ctype, curl, dom, filter, ftp, gd, gettext, hash, iconv, intl, json, mbstring, SPL, session, pcntl, standard, PDO, mysqlnd, pdo_sqlite, Phar, posix, Reflection, pdo_mysql, shmop, SimpleXML, soap, sockets, sodium, mysqli, sysvsem, tokenizer, xml, xmlreader, xmlwriter, zip, fileinfo, exif, Zend OPcache