Even though the option is disabled for users liking their own posts they can still like their messages.
I deactivated all the other extensions and its still the same. using flarum 1.5.
Flarum information
Flarum core 1.5.0
PHP version: 7.4.32
MySQL version: 8.0.30-cll-lve
Loaded extensions: Core, date, libxml, openssl, pcre, sqlite3, zlib, bz2, calendar, ctype, curl, hash, filter, ftp, gettext, gmp, SPL, iconv, pcntl, readline, Reflection, session, standard, shmop, SimpleXML, mbstring, tokenizer, xml, i360, bcmath, dom, fileinfo, gd, imap, intl, json, exif, mcrypt, mysqlnd, mysqli, PDO, pdo_mysql, pdo_sqlite, Phar, posix, sockets, xmlreader, xmlwriter, xsl, zip, ionCube Loader
+-----------------------------------+-----------------+--------+
| Flarum Extensions | | |
+-----------------------------------+-----------------+--------+
| ID | Version | Commit |
+-----------------------------------+-----------------+--------+
| askvortsov-auto-moderator | v0.1.2 | |
| flarum-suspend | v1.5.0 | |
| flarum-flags | v1.5.0 | |
| afrux-forum-widgets-core | v0.1.7 | |
| user-badges | dev-main | |
| traditional-rank-icons | dev-master | |
| sycho-profile-cover | v1.3.3 | |
| justoverclock-hashtag | 1.0.1 | |
| fof-user-bio | 1.1.1 | |
| fof-polls | 1.2.1 | |
| fof-oauth | 1.2.2 | |
| fof-nightmode | 1.5.0 | |
| fof-links | 1.1.2 | |
| fof-linguist | 1.0.4 | |
| fof-formatting | 1.0.2 | |
| flarumite-simple-discussion-views | 1.1.5 | |
| flarum-tags | v1.5.0 | |
| flarum-subscriptions | v1.5.0 | |
| flarum-sticky | v1.5.0 | |
| flarum-statistics | v1.5.1 | |
| flarum-package-manager | v1.0.0-beta.1.1 | |
| flarum-mentions | v1.5.0 | |
| flarum-markdown | v1.5.0 | |
| flarum-lock | v1.5.0 | |
| flarum-likes | v1.5.0 | |
| flarum-lang-turkish | 1.7.0 | |
| flarum-lang-english | v1.5.0 | |
| flarum-emoji | v1.5.0 | |
| flarum-bbcode | v1.5.0 | |
| flarum-approval | v1.5.0 | |
| datitisev-post-galleries | 1.0.0 | |
| blomstra-no-email-notifications | 0.1.0 | |
| antoinefr-online | v1.0.1 | |
| afrux-news-widget | v0.1.1 | |
+-----------------------------------+-----------------+--------+
