Update: I made some progress!
It turns out the blank page issue was caused by having nativephp/laravel installed — I had added it earlier while trying to configure an external PostgreSQL database. After removing the nativephp/laravel package, the blank screen issue is gone!
However, I’m now getting the following error:
could not find driver (Connection: pgsql, SQL: select * from "sessions" where "id" = 4d3PBwSM9WqqacCYmYhtOUvfNChmzWKNmhr5FaZk limit 1)
It looks like the app still can’t connect to the PostgreSQL database. Do I need to install something specific to enable the pgsql driver in the NativePHP environment?
Thanks again for your help!