When there are no ingress admission tickets available, trying to list current operations using db.currentOp() in mongosh will stall until a ticket is released. This can make it hard to diagnose servers. The current workaround is to use the currentOp admin command instead, but that command is deprecated.

Since version 6.2, mongosh implementation of db.currentOp() uses the $currentOp aggregation stage instead of the currentOp command. The aggregate command is one of the commands that require an ingress admission ticket, whereas the currentOp command can proceed without a ticket.

We need to either allow the aggregate command to proceed without a ticket if it uses the $currentOp stage, or "undeprecate" the currentOp command.