While trying out the base installer on a current git checkout, I found that it fails while trying to add the main page:
Could not insert main page: RevisionStore for my_wiki cannot be used with a DB connection for devwiki
(devwiki is the database name I selected for the target wiki; my_wiki is the default.)
Also showed these errors afterwards:
Notice: Uncommitted DB writes (transaction from WikiPage::doCreate). in /usr/local/var/www/w/includes/libs/rdbms/database/Database.php on line 3798 Notice: DB transaction writes or callbacks still pending (WikiPage::insertOn). in /usr/local/var/www/w/includes/libs/rdbms/database/Database.php on line 3804 Fatal error: Uncaught Wikimedia\Rdbms\DBTransactionError: Explicit transaction still active. A caller may have caught an error. in /usr/local/var/www/w/includes/libs/rdbms/loadbalancer/LoadBalancer.php:1245 Stack trace: #0 [internal function]: Wikimedia\Rdbms\LoadBalancer->Wikimedia\Rdbms\{closure}(Object(Wikimedia\Rdbms\DatabaseMysqli)) #1 /usr/local/var/www/w/includes/libs/rdbms/loadbalancer/LoadBalancer.php(1591): call_user_func_array(Object(Closure), Array) #2 /usr/local/var/www/w/includes/libs/rdbms/loadbalancer/LoadBalancer.php(1268): Wikimedia\Rdbms\LoadBalancer->forEachOpenMasterConnection(Object(Closure)) #3 [internal function]: Wikimedia\Rdbms\LoadBalancer->approveMasterChanges(Array) #4 /usr/local/var/www/w/includes/libs/rdbms/lbfactory/LBFactory.php(184): call_user_func_array(Array, Array) #5 [internal function]: Wikimedia\Rdbms\LBFactory->Wikimedia\Rdbms\{closure}(Object(Wikimedia\Rdbms\LoadBalancerSingle), 'approveMasterCh...', Array) #6 /usr/local/var/www/w/includes/libs/rdbms/lbfactory/LBFactorySingle.php( in /usr/local/var/www/w/includes/libs/rdbms/loadbalancer/LoadBalancer.php on line 1245