flarum.log, possibly unrelated:
[2019-10-02 14:12:58] production.ERROR: PDOException: SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add o
r update a child row: a foreign key constraint fails (`flarum_forumvalpacos`.`tags`, CONSTRAINT `tags_last_posted_discus
sion_id_foreign` FOREIGN KEY (`last_posted_discussion_id`) REFERENCES `discussions` (`id`) ON DELETE SET NULL)
MariaDB [flarum_forumvalpacos]> select * from flags;
+----+---------+----------+---------+--------+---------------+---------------------+
| id | post_id | type | user_id | reason | reason_detail | created_at |
+----+---------+----------+---------+--------+---------------+---------------------+
| 6 | 9 | approval | NULL | NULL | NULL | 2019-09-04 08:55:07 |
| 7 | 10 | approval | NULL | NULL | NULL | 2019-09-04 09:02:19 |
+----+---------+----------+---------+--------+---------------+---------------------+
Flarum core 0.1.0-beta.10
PHP version: 7.2.19-0ubuntu0.18.04.2
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, zip, Zend OPcache
+-------------------------------------------+-------------------+--------+
| Flarum Extensions | | |
+-------------------------------------------+-------------------+--------+
| ID | Version | Commit |
+-------------------------------------------+-------------------+--------+
| flarum-approval | v0.1.0-beta.8 | |
| flarum-bbcode | v0.1.0-beta.8 | |
| flarum-emoji | v0.1.0-beta.10 | |
| flarum-lang-english | v0.1.0-beta.10 | |
| flarum-flags | v0.1.0-beta.9 | |
| flarum-likes | v0.1.0-beta.9 | |
| flarum-lock | v0.1.0-beta.9 | |
| flarum-markdown | v0.1.0-beta.10 | |
| flarum-mentions | v0.1.0-beta.10 | |
| flarum-statistics | v0.1.0-beta.9 | |
| flarum-sticky | v0.1.0-beta.9 | |
| flarum-subscriptions | v0.1.0-beta.9 | |
| flarum-suspend | v0.1.0-beta.9 | |
| flagrow-sitemap | 0.2.0 | |
| fof-default-user-preferences | 0.2.0 | |
| migratetoflarum-canonical | 0.1.0 | |
| tiu-ram0n-flaneo-ext-brazilian-portuguese | 1.1.9 | |
| michaelbelgium-discussion-views | v0.1.0-beta.8.2 | |
| fof-profile-image-crop | 0.1.1 | |
| saleksin-auth-google | v0.1.0-beta.8.0.3 | |
| fof-masquerade | 0.3.3 | |
| flarum-auth-facebook | v0.1.0-beta.9 | |
| flarum-tags | v0.1.0-beta.10 | |
| fof-bbcode-details | 0.1.0 | |
| fof-drafts | 0.1.3 | |
| fof-formatting | 0.1.2 | |
| fof-user-bio | 0.1.3 | |
| matteocontrini-imgur-upload | v3.3.0 | |
| zerosonesfun-bbbbcode | 1.1.4.4 | |
| fof-user-directory | 0.3.3 | |
| fof-linguist | 0.4.0 | |
| jordanjay29-summaries | 0.3.1 | |
+-------------------------------------------+-------------------+--------+