With featureFlagExtensionsInsideHybridSearch=false, aggregating a view with a $facet containing $rankFusion or $scoreFusion aborts mongod:

Invariant failure: collectionAcquisitionReferences == 0 src/mongo/db/shard_role/transaction_resources.cpp:105 ~TransactionResources()

Repro script

mongod --setParameter featureFlagExtensionsInsideHybridSearch=false \
       --setParameter featureFlagRankFusionFull=true

Reproduced deterministically on master (standalone + resmoke). Flag-off $facet reparse executes the desugared $unionWith with the wrong acquisition context, leaking a collection acquisition.