1 files changed, 17 insertions, 2 deletions
diff --git a/src/validation.cpp b/src/validation.cpp
index 16cec9198a..a232ceb30f 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -3419,9 +3419,24 @@ void Chainstate::ResetBlockFailureFlags(CBlockIndex *pindex) {
 void Chainstate::TryAddBlockIndexCandidate(CBlockIndex* pindex)
 {
     AssertLockHeld(cs_main);
-    // If the block has more work than our tip, then it should be a candidate for most-work-chain.
-    if (m_chain.Tip() == nullptr || !setBlockIndexCandidates.value_comp()(pindex, m_chain.Tip())) {
+    // The block only is a candidate for the most-work-chain if it has more work than our current tip.
+    if (m_chain.Tip() != nullptr && setBlockIndexCandidates.value_comp()(pindex, m_chain.Tip())) {
+        return;
+    }
+
+    bool is_active_chainstate = this == &m_chainman.ActiveChainstate();
+    if (is_active_chainstate) {
+        // The active chainstate should always add entries that have more
+        // work than the tip.
         setBlockIndexCandidates.insert(pindex);
+    } else if (!m_disabled) {
+        // For the background chainstate, we only consider connecting blocks
+        // towards the snapshot base (which can't be nullptr or else we'll
+        // never make progress).
+        const CBlockIndex* snapshot_base = Assert(m_chainman.GetSnapshotBaseBlock());
+        if (snapshot_base->GetAncestor(pindex->nHeight) == pindex) {
+            setBlockIndexCandidates.insert(pindex);
+        }
     }
 }