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A key technique for proving unsolvability in classical planning are dead-end detectors \Delta: effectively testable criteria sufficient for unsolvability, pruning (some) unsolvable states during search. Related to this, a recent proposal is the identification of traps prior to search, compact representations of non-goal state sets T that cannot be escaped. Here, we create new synergy across these ideas. We define a generalized concept of traps, relative to a given dead-end detector \Delta, where T can be escaped, but only into dead-end states detected by \Delta. We show how to learn compact representations of such T during search, extending the reach of \Delta. Our experiments show that this can be quite beneficial. It improves coverage for many unsolvable benchmark planning domains and dead-end detectors \Delta, in particular on resource-constrained domains where it outperforms the state of the art.