I have pgadmin 6.15 deployed in kubernetes. Users can authenticate to databases using the pgpass file and a server that is preconfigured on startup. A user can either leave the page, or close their browser, but the underlying connection to the database is kept intact indefinitely. At a certain point (undetermined), there are too many connections open to databases that pgadmin is unable to connect to any database. The connection spins and the logs show:

INFO	pgadmin:	Connection Request for server#1
INFO	pgadmin:	Waiting for a lock.

The lock is never achieved and eventually the connection request will timeout.
I have the following settings in place for pgadmin:

SESSION_EXPIRATION_TIME = 1
MAX_SESSION_IDLE_TIME = 60
CHECK_SESSION_FILES_INTERVAL = 24
USER_INACTIVITY_TIMEOUT = 900

In this case, it does not appear that MAX_SESSION_IDLE_TIME is being honored.
This behavior has been seen in all PgAdmin versions we've run (6.12+).