The manual, in the section “Searching -> Card State”, says:
is:learn is:review
cards that have lapsed and are awaiting relearning
-is:learn is:review
review cards, not including lapsed cards
But it seems to me that “is:learn” is not matching lapsed cards anymore. The first mentioned search always results in no cards being found (even if there are lapsed cards still awaiting relearning). And the second mentioned search matches the same number of cards of the search “is: review”.
That is the case for the beta version and also for the stable version 2.1.26.