Can cursors return the same document more than once in MongoDB 4.0?

Is it something we have to concern in version as of 4.0?

Read Isolation, Consistency, and Recency — MongoDB Manual

MongoDB cursors can return the same document more than once in some situations. As a cursor returns documents other operations may interleave with the query. If some of these operations change the indexed field on the index used by the query; then the cursor will return the same document more than once.

https://docs.mongodb.com/manual/core/read-isolation-consistency-recency/#cursor-snapshot

The docs you are quoting are for the current version (4.2) so yes, there is no guarantee of a single point in time view when you iterate over a cursor unless you are in a transaction or otherwise force a stronger readConcern.

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