Serious? Are you fucking kidding me? #SQLite3 #Drupal #WTF

With a bit python it was possible to transform a Druapl 8's sqlite3 dump into a sql file that I could import into MariaDB 10.3. Surprisingly the whole multi domain and multi language website seemed to work quite fine in frontend and backend on a first and second look. Just the dblog is filling with unserialize errors from the key value store.
Looks like there are entries which do not get out of sqlite3 correctly. Neither through dump, nor cli.

A sqlite3 database dump
$ sqlite3 sites/default/files/.ht.sqlite .dump | grep user.entity_type
INSERT INTO "key_value" VALUES('entity.definitions.installed','user.entity_type','O:36:"Drupal\Core\Entity\ContentEntityType":37:{s:15:"');

Query the database directly with the sqlite3 cli
$ sqlite3 sites/default/files/.ht.sqlite "SELECT * FROM key_value WHERE name = 'user.entity_type'"
entity.definitions.installed|user.entity_type|O:36:"Drupal\Core\Entity\ContentEntityType":37:{s:15:"

Actually this is the same like the sqlite3 cli
$ ../bin/drush sql-query "SELECT * FROM key_value WHERE name = 'user.entity_type'"
entity.definitions.installed|user.entity_type|O:36:"Drupal\Core\Entity\ContentEntityType":37:{s:15:"

Is this Drupal 8 Magic? :-!
$ ../bin/drush php-eval "\$r=db_query('SELECT * FROM key_value WHERE name = \"user.entity_type\"')->fetchAll(); print_r(\$r[0]->value);"
O:36:"Drupal\Core\Entity\ContentEntityType":37:{s:15:"*static_cache";b:1;s:15:"*render_cache";b:1;s:19:"*persistent_cache";b:1;s:14:"*entity_keys";a:6:{s:2:"id";s:3:"uid";s:8:"langcode";s:8:"langcode";s:4:"uuid";s:4:"uuid";s:8:"revision";s:0:"";s:6:"bundle";s:0:"";s:16:"default_langcode";s:16:"default_langcode";}s:5:"*id";s:4:"user";s:16:"*originalClass";s:23:"Drupal\user\Entity\User";s:11:"*handlers";a:9:{s:7:"storage";s:23:"Drupal\user\UserStorage";s:14:"storage_schema";s:29:"Drupal\user\UserStorageSchema";s:6:"access";s:36:"Drupal\user\UserAccessControlHandler";s:12:"list_builder";s:27:"Drupal\user\UserListBuilder";s:10:"views_data";s:25:"Drupal\user\UserViewsData";s:14:"route_provider";a:1:{s:4:"html";s:36:"Drupal\user\Entity\UserRouteProvider";}s:4:"form";a:3:{s:7:"default";s:23:"Drupal\user\ProfileForm";s:6:"cancel";s:31:"Drupal\user\Form\UserCancelForm";s:8:"register";s:24:"Drupal\user\RegisterForm";}s:11:"translation";s:37:"Drupal\user\ProfileTranslationHandler";s:12:"view_builder";s:36:"Drupal\Core\Entity\EntityViewBuilder";}s:19:"*admin_permission";s:16:"administer users";s:25:"*permission_granularity";s:11:"entity_type";s:8:"*links";a:4:{s:9:"canonical";s:12:"/user/{user}";s:9:"edit-form";s:17:"/user/{user}/edit";s:11:"cancel-form";s:19:"/user/{user}/cancel";s:10:"collection";s:13:"/admin/people";}s:17:"*label_callback";s:16:"user_format_name";s:21:"*bundle_entity_type";N;s:12:"*bundle_of";N;s:15:"*bundle_label";N;s:13:"*base_table";s:5:"users";s:22:"*revision_data_table";N;s:17:"*revision_table";N;s:13:"*data_table";s:16:"users_field_data";s:15:"*translatable";b:1;s:19:"*show_revision_ui";b:0;s:8:"*label";O:48:"Drupal\Core\StringTranslation\TranslatableMarkup":3:{s:9:"*string";s:4:"User";s:12:"*arguments";a:0:{}s:10:"*options";a:0:{}}s:19:"*label_collection";s:0:"";s:17:"*label_singular";s:0:"";s:15:"*label_plural";s:0:"";s:14:"*label_count";a:0:{}s:15:"*uri_callback";N;s:8:"*group";s:7:"content";s:14:"*group_label";O:48:"Drupal\Core\StringTranslation\TranslatableMarkup":3:{s:9:"*string";s:7:"Content";s:12:"*arguments";a:0:{}s:10:"*options";a:1:{s:7:"context";s:17:"Entity type group";}}s:22:"*field_ui_base_route";s:22:"entity.user.admin_form";s:26:"*common_reference_target";b:1;s:22:"*list_cache_contexts";a:0:{}s:18:"*list_cache_tags";a:1:{i:0;s:9:"user_list";}s:14:"*constraints";a:1:{s:13:"EntityChanged";N;}s:13:"*additional";a:0:{}s:8:"*class";s:23:"Drupal\user\Entity\User";s:11:"*provider";s:4:"user";s:20:"*stringTranslation";N;}
How to get a complete dump from the sqlite3 database?

Where has my beloved TYPO3 gone?