The issue
When a user receives an email notification and navigates to the URL within the email it leads to a broken page.
Example URL within the email: https://www.casfans.co.uk/d/217/13
Had a look and can't see anything wrong and nothing is being logged anywhere.
Flarum information
Flarum core 1.6.3
PHP version: 7.3.31-1~deb10u3
MySQL version: 5.5.5-10.3.38-MariaDB-0+deb10u1
Loaded extensions: Core, date, libxml, openssl, pcre, zlib, filter, hash, pcntl, Reflection, SPL, sodium, session, standard, mysqlnd, PDO, xml, calendar, ctype, curl, dom, mbstring, fileinfo, ftp, gd, gettext, iconv, json, exif, mysqli, pdo_mysql, Phar, posix, readline, shmop, SimpleXML, sockets, sysvmsg, sysvsem, sysvshm, tokenizer, wddx, xmlreader, xmlwriter, xsl, Zend OPcache
+---------------------------------+---------+--------+
| Flarum Extensions | | |
+---------------------------------+---------+--------+
| ID | Version | Commit |
+---------------------------------+---------+--------+
| flarum-likes | v1.6.1 | |
| flarum-flags | v1.6.1 | |
| flarum-suspend | v1.6.1 | |
| clarkwinkelmann-likes-received | 1.0.2 | |
| flarum-tags | v1.6.1 | |
| fof-spamblock | 1.1.0 | |
| flarum-approval | v1.6.1 | |
| afrux-forum-widgets-core | v0.1.7 | |
| v17development-seo | v1.8.0 | |
| tohsakarat-tags-filter | v1.0.3 | |
| the-turk-flamoji | 1.0.4 | |
| michaelbelgium-discussion-views | v7.2 | |
| kyrne-whisper | 0.1.4 | |
| justoverclock-user-statistics | 0.1.9 | |
| ianm-synopsis | 1.2.2 | |
| ianm-level-ranks | 1.1.0 | |
| ianm-html-head | 1.1.0 | |
| fof-user-directory | 1.2.3 | |
| fof-upload | 1.2.3 | |
| fof-stopforumspam | 1.2.3 | |
| fof-sitemap | 1.0.3 | |
| fof-recaptcha | 1.1.0 | |
| fof-reactions | 1.1.3 | |
| fof-polls | 1.3.0 | |
| fof-pages | 1.0.4 | |
| fof-merge-discussions | 1.3.1 | |
| fof-links | 1.1.3 | |
| fof-formatting | 1.0.2 | |
| fof-analytics | 1.1.0 | |
| flarum-subscriptions | v1.6.3 | |
| flarum-sticky | v1.6.1 | |
| flarum-statistics | v1.6.1 | |
| flarum-mentions | v1.6.3 | |
| flarum-markdown | v1.6.1 | |
| flarum-lock | v1.6.1 | |
| flarum-lang-english | v1.6.0 | |
| flarum-bbcode | v1.6.0 | |
| ecnu-im-sticky-sidenav | v1.1.0 | |
| askvortsov-moderator-warnings | v0.6.1 | |
| afrux-online-users-widget | v0.1.6 | |
| afrux-news-widget | v0.1.1 | |
| afrux-forum-stats-widget | v0.1.1 | |
+---------------------------------+---------+--------+
Base URL: https://www.casfans.co.uk
Installation path: <removed>
Queue driver: sync
Session driver: file
Mail driver: smtp
Debug mode: off