diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/core.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/core.rs
index 9fd7de11b4..4e850be3c3 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/core.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/core.rs
@@ -11,21 +11,21 @@ use super::{
     IndexedDbObjectStoreMetadata, IndexedDbRuntimeArray, IndexedDbStorageScope, IndexedDbValue,
     IndexedDbWrapperKind, Key, KeyPath, ObjectStoreInfo, PreparedObjectStoreWrite,
     PreparedObjectStoreWriteError, TransactionHandle, TransactionMode,
-    context_host_ptr_from_global_bridge, dispatch_version_change_event,
-    global_constructor_prototype, indexed_db_database_store_metadata,
-    indexed_db_object_store_metadata, indexed_db_runtime_array, indexed_db_typed_execution_owner,
-    indexed_db_typed_storage_scope, new_null_prototype_object, object_bool_property,
-    object_hidden_value, object_number_property, object_property_as_object, object_string_property,
-    push_unique_object_to_indexed_db_runtime_array, register_indexed_db_cursor_lifecycle,
-    register_indexed_db_database_lifecycle, register_indexed_db_index_lifecycle,
-    register_indexed_db_key_range_lifecycle, register_indexed_db_object_store_lifecycle,
-    register_indexed_db_request_lifecycle, register_indexed_db_transaction_lifecycle,
-    register_indexed_db_wrapper, register_indexed_db_wrapper_with_owner,
-    remove_indexed_db_database_index_metadata, remove_indexed_db_database_store_metadata,
-    replace_indexed_db_database_metadata, replace_indexed_db_runtime_array,
-    set_indexed_db_database_index_metadata, set_indexed_db_database_store_metadata,
-    set_indexed_db_internal_object_property, set_indexed_db_object_store_metadata,
-    set_indexed_db_request_surface_value, set_indexed_db_slot_value, v8_string, v8str,
+    context_host_ptr_from_global_bridge, global_constructor_prototype,
+    indexed_db_database_store_metadata, indexed_db_object_store_metadata, indexed_db_runtime_array,
+    indexed_db_typed_execution_owner, indexed_db_typed_storage_scope, new_null_prototype_object,
+    object_bool_property, object_hidden_value, object_number_property, object_property_as_object,
+    object_string_property, push_unique_object_to_indexed_db_runtime_array,
+    register_indexed_db_cursor_lifecycle, register_indexed_db_database_lifecycle,
+    register_indexed_db_index_lifecycle, register_indexed_db_key_range_lifecycle,
+    register_indexed_db_object_store_lifecycle, register_indexed_db_request_lifecycle,
+    register_indexed_db_transaction_lifecycle, register_indexed_db_wrapper,
+    register_indexed_db_wrapper_with_owner, remove_indexed_db_database_index_metadata,
+    remove_indexed_db_database_store_metadata, replace_indexed_db_database_metadata,
+    replace_indexed_db_runtime_array, set_indexed_db_database_index_metadata,
+    set_indexed_db_database_store_metadata, set_indexed_db_internal_object_property,
+    set_indexed_db_object_store_metadata, set_indexed_db_request_surface_value,
+    set_indexed_db_slot_value, v8_string, v8str,
 };
 use std::collections::BTreeSet;
 use v8::{ValueDeserializerHelper, ValueSerializerHelper};
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/core/registry.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/core/registry.rs
index d4080aee55..a075081e77 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/core/registry.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/core/registry.rs
@@ -4,7 +4,7 @@ mod connections;
 mod readwrite;
 
 pub(in crate::context_bootstrap::indexed_db) use self::connections::{
-    database_registry_key, dispatch_version_change_to_open_connections,
+    database_registry_key, enqueue_version_change_to_open_connections,
     has_open_database_connections_for_key, open_database_connection_version_for_key,
     register_blocked_database_context, register_open_database_connection,
     unregister_blocked_database_context, unregister_open_database_connection,
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/core/registry/connections.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/core/registry/connections.rs
index 461f5f4031..609150b712 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/core/registry/connections.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/core/registry/connections.rs
@@ -1,4 +1,8 @@
 use super::*;
+use crate::context_bootstrap::indexed_db::{
+    enqueue_blocked_recheck_task, enqueue_version_change_task,
+    set_indexed_db_blocked_notifications_pending,
+};
 
 pub(in crate::context_bootstrap::indexed_db) fn database_registry_key(
     origin: &str,
@@ -33,28 +37,25 @@ pub(in crate::context_bootstrap::indexed_db) fn open_database_connection_version
         .max()
 }
 
-pub(in crate::context_bootstrap::indexed_db) fn dispatch_version_change_to_open_connections(
-    scope: &mut v8::PinScope<'_, '_>,
+pub(in crate::context_bootstrap::indexed_db) fn enqueue_version_change_to_open_connections<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
     key: &str,
     old_version: u64,
     new_version: Option<u64>,
+    blocked_task: v8::Local<'s, v8::Object>,
 ) {
+    set_indexed_db_blocked_notifications_pending(scope, blocked_task, true);
     let Some(host_ptr) = context_host_ptr_from_global_bridge(scope) else {
         for database in local_open_database_connections_for_key(scope, key) {
-            let _ = dispatch_version_change_event(
-                scope,
-                database,
-                "versionchange",
-                old_version,
-                new_version,
-            );
+            enqueue_version_change_task(scope, database, old_version, new_version);
         }
+        enqueue_blocked_recheck_task(scope, blocked_task);
         return;
     };
 
     // Connections share backend coordination but retain the V8 realm that
-    // created each IDBDatabase wrapper. Snapshot roots before invoking script
-    // so close()/navigation can mutate the coordinator during dispatch.
+    // created each IDBDatabase wrapper. Each connection gets its own task and
+    // checkpoint; its callback may close other connections before their turn.
     let connections = unsafe { &*host_ptr }.indexed_db_open_connection_snapshots(scope, key);
     for connection in connections {
         if !unsafe { &*host_ptr }
@@ -70,14 +71,9 @@ pub(in crate::context_bootstrap::indexed_db) fn dispatch_version_change_to_open_
             continue;
         }
         let database = v8::Local::new(target_scope, &connection.database);
-        let _ = dispatch_version_change_event(
-            target_scope,
-            database,
-            "versionchange",
-            old_version,
-            new_version,
-        );
+        enqueue_version_change_task(target_scope, database, old_version, new_version);
     }
+    enqueue_blocked_recheck_task(scope, blocked_task);
 }
 
 pub(in crate::context_bootstrap::indexed_db) fn register_open_database_connection(
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks.rs
index 294d158357..21d9b835e8 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks.rs
@@ -17,8 +17,8 @@ use super::{
     close_indexed_db_database_connection, create_database_object, create_transaction_object,
     database_handle_from_value, database_registry_key, define_non_enumerable_value_property,
     deserialize_js_value, dispatch_idb_named_event, dispatch_version_change_event,
-    dispatch_version_change_to_open_connections, dom_exception_value, dom_string_list_values,
-    enforce_object_store_unique_constraints, flush_databases_settle_task,
+    dom_exception_value, dom_string_list_values, enforce_object_store_unique_constraints,
+    enqueue_version_change_to_open_connections, flush_databases_settle_task,
     has_open_database_connections_for_key, index_cursor_snapshot, indexed_db_blocked_task_payload,
     indexed_db_index_info, indexed_db_open_task_payload, indexed_db_request_dispatch_task_request,
     indexed_db_request_transaction_object, indexed_db_runtime_array,
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/dispatch/router.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/dispatch/router.rs
index adbda889b9..306ab2d3ec 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/dispatch/router.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/dispatch/router.rs
@@ -53,6 +53,8 @@ fn flush_indexed_db_task<'s>(
         IndexedDbTaskKind::Open => flush_open_task(scope, task),
         IndexedDbTaskKind::OpenBlocked => flush_open_blocked_task(scope, task),
         IndexedDbTaskKind::DeleteBlocked => flush_delete_blocked_task(scope, task),
+        IndexedDbTaskKind::VersionChange => flush_version_change_task(scope, task),
+        IndexedDbTaskKind::BlockedRecheck => flush_blocked_recheck_task(scope, task),
         IndexedDbTaskKind::DrainBlockedOpens => flush_drain_blocked_open_requests_task(scope),
         IndexedDbTaskKind::DatabasesSettle => flush_databases_settle_task(scope, task),
         IndexedDbTaskKind::TransactionStart => flush_transaction_start_task(scope, task),
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete.rs
index 49282f4132..2a888197c5 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete.rs
@@ -5,7 +5,8 @@ mod delete;
 mod open;
 
 pub(in crate::context_bootstrap::indexed_db) use self::blocked::{
-    flush_delete_blocked_task, flush_drain_blocked_open_requests_task, flush_open_blocked_task,
+    flush_blocked_recheck_task, flush_delete_blocked_task, flush_drain_blocked_open_requests_task,
+    flush_open_blocked_task, flush_version_change_task,
 };
 pub(in crate::context_bootstrap::indexed_db) use self::delete::execute_delete_database_request;
 pub(in crate::context_bootstrap::indexed_db) use self::open::execute_open_request;
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked.rs
index 8e68d87a53..24abc8c9e1 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked.rs
@@ -3,6 +3,7 @@ use super::*;
 mod delete_task;
 mod drain;
 mod event;
+mod notifications;
 mod open_task;
 
 pub(super) fn blocked_task_storage_scope<'s>(
@@ -14,4 +15,7 @@ pub(super) fn blocked_task_storage_scope<'s>(
 
 pub(in crate::context_bootstrap::indexed_db) use self::delete_task::flush_delete_blocked_task;
 pub(in crate::context_bootstrap::indexed_db) use self::drain::flush_drain_blocked_open_requests_task;
+pub(in crate::context_bootstrap::indexed_db) use self::notifications::{
+    flush_blocked_recheck_task, flush_version_change_task,
+};
 pub(in crate::context_bootstrap::indexed_db) use self::open_task::flush_open_blocked_task;
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/delete_task.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/delete_task.rs
index f1b4be2399..8341ba6b01 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/delete_task.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/delete_task.rs
@@ -20,16 +20,6 @@ pub(in crate::context_bootstrap::indexed_db) fn flush_delete_blocked_task<'s>(
         );
         return;
     }
-    dispatch_version_change_to_open_connections(scope, &key, payload.old_version, None);
-    if !has_open_database_connections_for_key(scope, &key) {
-        delete::execute_delete_database_request(
-            scope,
-            payload.request,
-            storage_scope,
-            payload.name,
-        );
-        return;
-    }
     push_unique_object_to_indexed_db_runtime_array(
         scope,
         IndexedDbRuntimeArray::BlockedOpenQueue,
@@ -37,6 +27,6 @@ pub(in crate::context_bootstrap::indexed_db) fn flush_delete_blocked_task<'s>(
     );
     let owner = indexed_db_typed_task_execution_owner(scope, task)
         .expect("blocked delete task must retain its IndexedDB execution owner");
-    register_blocked_database_context(scope, key, owner);
-    event::dispatch_blocked_once(scope, payload.request, payload.old_version, None);
+    register_blocked_database_context(scope, key.clone(), owner);
+    enqueue_version_change_to_open_connections(scope, &key, payload.old_version, None, task);
 }
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/drain.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/drain.rs
index 19d5fece6b..7b1795bd0a 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/drain.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/drain.rs
@@ -8,6 +8,7 @@ pub(in crate::context_bootstrap::indexed_db) fn flush_drain_blocked_open_request
         return;
     };
     let next = v8::Array::new(scope, 0);
+    let mut waiting_keys = std::collections::BTreeSet::new();
     for index in 0..queue.length() {
         let Some(value) = queue.get_index(scope, index) else {
             continue;
@@ -17,7 +18,13 @@ pub(in crate::context_bootstrap::indexed_db) fn flush_drain_blocked_open_request
         };
         let database_key = indexed_db_blocked_task_payload(scope, task)
             .map(|payload| database_registry_key(&payload.origin, &payload.name));
-        if !try_execute_unblocked_request(scope, task) {
+        let waiting_for_earlier = database_key
+            .as_ref()
+            .is_some_and(|key| waiting_keys.contains(key));
+        if waiting_for_earlier || !try_execute_unblocked_request(scope, task) {
+            if let Some(key) = database_key {
+                waiting_keys.insert(key);
+            }
             let _ = next.set_index(scope, next.length(), task.into());
         } else {
             if let Some(database_key) = database_key.as_deref() {
@@ -50,6 +57,9 @@ fn try_execute_unblocked_request_in_owner_scope<'s>(
     let Some(payload) = indexed_db_blocked_task_payload(scope, task) else {
         return false;
     };
+    if payload.notifications_pending {
+        return false;
+    }
     let key = database_registry_key(&payload.origin, &payload.name);
     if has_open_database_connections_for_key(scope, &key) {
         return false;
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/notifications.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/notifications.rs
new file mode 100644
index 0000000000..f51b6adfcc
--- /dev/null
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/notifications.rs
@@ -0,0 +1,47 @@
+use super::*;
+use crate::context_bootstrap::indexed_db::{
+    INDEXED_DB_DATABASE_CLOSED_SLOT, indexed_db_blocked_recheck_task_payload,
+    indexed_db_version_change_task_payload, set_indexed_db_blocked_notifications_pending,
+};
+
+pub(in crate::context_bootstrap::indexed_db) fn flush_version_change_task<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    task: v8::Local<'s, v8::Object>,
+) {
+    let Some((database, old_version, new_version)) =
+        indexed_db_version_change_task_payload(scope, task)
+    else {
+        return;
+    };
+    if object_bool_property(scope, database, INDEXED_DB_DATABASE_CLOSED_SLOT).unwrap_or(false) {
+        return;
+    }
+    let _ =
+        dispatch_version_change_event(scope, database, "versionchange", old_version, new_version);
+}
+
+pub(in crate::context_bootstrap::indexed_db) fn flush_blocked_recheck_task<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    task: v8::Local<'s, v8::Object>,
+) {
+    let Some(blocked_task) = indexed_db_blocked_recheck_task_payload(scope, task) else {
+        return;
+    };
+    let Some(payload) = indexed_db_blocked_task_payload(scope, blocked_task) else {
+        return;
+    };
+    // All connection notifications precede this task in the same IndexedDB
+    // source, including stale tickets discarded when their realm is retired.
+    set_indexed_db_blocked_notifications_pending(scope, blocked_task, false);
+    let key = database_registry_key(&payload.origin, &payload.name);
+    if !has_open_database_connections_for_key(scope, &key) {
+        enqueue_drain_blocked_open_requests_task(scope);
+        return;
+    }
+    event::dispatch_blocked_once(
+        scope,
+        payload.request,
+        payload.old_version,
+        payload.new_version,
+    );
+}
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/open_task.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/open_task.rs
index 7cf6996c2e..a5e174f9f4 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/open_task.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/open_delete/blocked/open_task.rs
@@ -24,22 +24,6 @@ pub(in crate::context_bootstrap::indexed_db) fn flush_open_blocked_task<'s>(
         );
         return;
     }
-    dispatch_version_change_to_open_connections(
-        scope,
-        &key,
-        payload.old_version,
-        Some(new_version),
-    );
-    if !has_open_database_connections_for_key(scope, &key) {
-        open::execute_open_request(
-            scope,
-            payload.request,
-            storage_scope,
-            payload.name,
-            payload.version,
-        );
-        return;
-    }
     push_unique_object_to_indexed_db_runtime_array(
         scope,
         IndexedDbRuntimeArray::BlockedOpenQueue,
@@ -47,11 +31,12 @@ pub(in crate::context_bootstrap::indexed_db) fn flush_open_blocked_task<'s>(
     );
     let owner = indexed_db_typed_task_execution_owner(scope, task)
         .expect("blocked open task must retain its IndexedDB execution owner");
-    register_blocked_database_context(scope, key, owner);
-    event::dispatch_blocked_once(
+    register_blocked_database_context(scope, key.clone(), owner);
+    enqueue_version_change_to_open_connections(
         scope,
-        payload.request,
+        &key,
         payload.old_version,
         Some(new_version),
+        task,
     );
 }
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/queue/blocked.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/queue/blocked.rs
index 00140e8633..f6b21ca38e 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/queue/blocked.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/tasks/queue/blocked.rs
@@ -1,4 +1,35 @@
 use super::*;
+use crate::context_bootstrap::indexed_db::{
+    register_indexed_db_blocked_recheck_task, register_indexed_db_version_change_task,
+};
+
+pub(in crate::context_bootstrap::indexed_db) fn enqueue_version_change_task<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    database: v8::Local<'s, v8::Object>,
+    old_version: u64,
+    new_version: Option<u64>,
+) {
+    let Some(context) = database.get_creation_context(scope) else {
+        return;
+    };
+    let scope = &mut v8::ContextScope::new(scope, context);
+    let task = v8::Object::new(scope);
+    register_indexed_db_version_change_task(scope, task, database, old_version, new_version);
+    enqueue_indexed_db_task(scope, task);
+}
+
+pub(in crate::context_bootstrap::indexed_db) fn enqueue_blocked_recheck_task<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    blocked_task: v8::Local<'s, v8::Object>,
+) {
+    let Some(context) = blocked_task.get_creation_context(scope) else {
+        return;
+    };
+    let scope = &mut v8::ContextScope::new(scope, context);
+    let task = v8::Object::new(scope);
+    register_indexed_db_blocked_recheck_task(scope, task, blocked_task);
+    enqueue_indexed_db_task(scope, task);
+}
 
 pub(in crate::context_bootstrap::indexed_db) fn enqueue_blocked_open_task<'s>(
     scope: &mut v8::PinScope<'s, '_>,
diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/typed_state.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/typed_state.rs
index 2a3db2941f..1f1249d68a 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/typed_state.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/typed_state.rs
@@ -35,6 +35,8 @@ pub(super) enum IndexedDbTaskKind {
     Open,
     OpenBlocked,
     DeleteBlocked,
+    VersionChange,
+    BlockedRecheck,
     DrainBlockedOpens,
     DatabasesSettle,
     TransactionStart,
@@ -187,6 +189,8 @@ impl IndexedDbTaskState {
             | IndexedDbTaskKind::Open
             | IndexedDbTaskKind::OpenBlocked
             | IndexedDbTaskKind::DeleteBlocked
+            | IndexedDbTaskKind::VersionChange
+            | IndexedDbTaskKind::BlockedRecheck
             | IndexedDbTaskKind::DrainBlockedOpens
             | IndexedDbTaskKind::DatabasesSettle
             | IndexedDbTaskKind::TransactionStart
@@ -268,6 +272,7 @@ struct IndexedDbBlockedTaskPayload {
     version: Option<u64>,
     old_version: u64,
     new_version: Option<u64>,
+    notifications_pending: bool,
 }
 
 impl IndexedDbBlockedTaskPayload {
@@ -288,6 +293,7 @@ impl IndexedDbBlockedTaskPayload {
             version,
             old_version,
             new_version,
+            notifications_pending: false,
         }
     }
 }
@@ -299,6 +305,13 @@ pub(super) struct IndexedDbBlockedTaskPayloadLocals<'s> {
     pub(super) version: Option<u64>,
     pub(super) old_version: u64,
     pub(super) new_version: Option<u64>,
+    pub(super) notifications_pending: bool,
+}
+
+struct IndexedDbVersionChangeTaskPayload {
+    database: v8::Global<v8::Object>,
+    old_version: u64,
+    new_version: Option<u64>,
 }
 
 struct IndexedDbTransactionTaskPayload {
@@ -545,6 +558,8 @@ pub(super) struct IndexedDbRuntimeStateTable {
     request_dispatch_tasks: BTreeMap<IndexedDbTaskId, IndexedDbRequestDispatchTaskPayload>,
     open_tasks: BTreeMap<IndexedDbTaskId, IndexedDbOpenTaskPayload>,
     blocked_tasks: BTreeMap<IndexedDbTaskId, IndexedDbBlockedTaskPayload>,
+    version_change_tasks: BTreeMap<IndexedDbTaskId, IndexedDbVersionChangeTaskPayload>,
+    blocked_recheck_tasks: BTreeMap<IndexedDbTaskId, v8::Global<v8::Object>>,
     transaction_tasks: BTreeMap<IndexedDbTaskId, IndexedDbTransactionTaskPayload>,
     requests: BTreeMap<IndexedDbObjectId, IndexedDbRequestLifecycleState>,
     transactions: BTreeMap<IndexedDbObjectId, IndexedDbTransactionLifecycleState>,
@@ -1190,9 +1205,99 @@ pub(super) fn indexed_db_blocked_task_payload<'s>(
         version: payload.version,
         old_version: payload.old_version,
         new_version: payload.new_version,
+        notifications_pending: payload.notifications_pending,
     })
 }
 
+pub(super) fn set_indexed_db_blocked_notifications_pending<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    blocked_task: v8::Local<'s, v8::Object>,
+    pending: bool,
+) {
+    let Some(id) = indexed_db_typed_task_id(scope, blocked_task) else {
+        return;
+    };
+    let table = indexed_db_runtime_state_table_for_object(scope, blocked_task);
+    if let Some(payload) = table.borrow_mut().blocked_tasks.get_mut(&id) {
+        payload.notifications_pending = pending;
+    }
+}
+
+pub(super) fn register_indexed_db_version_change_task<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    task: v8::Local<'s, v8::Object>,
+    database: v8::Local<'s, v8::Object>,
+    old_version: u64,
+    new_version: Option<u64>,
+) {
+    let owner = indexed_db_typed_execution_owner(scope, database)
+        .expect("versionchange task retains its database owner");
+    let storage_scope = indexed_db_typed_storage_scope(scope, database);
+    let id = register_indexed_db_task_with_owner(
+        scope,
+        task,
+        IndexedDbTaskKind::VersionChange,
+        owner,
+        storage_scope,
+    );
+    let table = indexed_db_runtime_state_table_for_object(scope, task);
+    table.borrow_mut().version_change_tasks.insert(
+        id,
+        IndexedDbVersionChangeTaskPayload {
+            database: v8::Global::new(scope, database),
+            old_version,
+            new_version,
+        },
+    );
+}
+
+pub(super) fn indexed_db_version_change_task_payload<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    task: v8::Local<'s, v8::Object>,
+) -> Option<(v8::Local<'s, v8::Object>, u64, Option<u64>)> {
+    let id = indexed_db_typed_task_id(scope, task)?;
+    let table = indexed_db_runtime_state_table_for_object(scope, task);
+    let table = table.borrow();
+    let payload = table.version_change_tasks.get(&id)?;
+    Some((
+        v8::Local::new(scope, &payload.database),
+        payload.old_version,
+        payload.new_version,
+    ))
+}
+
+pub(super) fn register_indexed_db_blocked_recheck_task<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    task: v8::Local<'s, v8::Object>,
+    blocked_task: v8::Local<'s, v8::Object>,
+) {
+    let owner = indexed_db_typed_task_execution_owner(scope, blocked_task)
+        .expect("blocked recheck retains the requesting task owner");
+    let storage_scope = indexed_db_typed_task_storage_scope(scope, blocked_task);
+    let id = register_indexed_db_task_with_owner(
+        scope,
+        task,
+        IndexedDbTaskKind::BlockedRecheck,
+        owner,
+        storage_scope,
+    );
+    let table = indexed_db_runtime_state_table_for_object(scope, task);
+    table
+        .borrow_mut()
+        .blocked_recheck_tasks
+        .insert(id, v8::Global::new(scope, blocked_task));
+}
+
+pub(super) fn indexed_db_blocked_recheck_task_payload<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    task: v8::Local<'s, v8::Object>,
+) -> Option<v8::Local<'s, v8::Object>> {
+    let id = indexed_db_typed_task_id(scope, task)?;
+    let table = indexed_db_runtime_state_table_for_object(scope, task);
+    let table = table.borrow();
+    Some(v8::Local::new(scope, table.blocked_recheck_tasks.get(&id)?))
+}
+
 pub(super) fn register_indexed_db_transaction_task<'s>(
     scope: &mut v8::PinScope<'s, '_>,
     task: v8::Local<'s, v8::Object>,
@@ -1248,6 +1353,8 @@ pub(super) fn unregister_indexed_db_task<'s>(
     table.open_tasks.remove(&id);
     table.blocked_tasks.remove(&id);
     table.transaction_tasks.remove(&id);
+    table.blocked_recheck_tasks.remove(&id);
+    table.version_change_tasks.remove(&id);
 }
 
 pub(super) fn replace_indexed_db_database_metadata<'s>(
diff --git a/moli-renderer-v8/src/runtime/page_vm/tests/indexed_db.rs b/moli-renderer-v8/src/runtime/page_vm/tests/indexed_db.rs
index da348bd420..6227e77b30 100644
--- a/moli-renderer-v8/src/runtime/page_vm/tests/indexed_db.rs
+++ b/moli-renderer-v8/src/runtime/page_vm/tests/indexed_db.rs
@@ -632,3 +632,72 @@ fn indexed_db_rejects_a_real_page_vm_replacement_identity_collision() {
         },
     );
 }
+
+#[tokio::test(flavor = "current_thread")]
+async fn indexed_db_retired_versionchange_notification_does_not_strand_open_request() {
+    run_page_vm_async_test(async move {
+        let loader = crate::network::ResourceRequestClient::new(&FetchConfig::default())
+            .expect("loader");
+        let manager = crate::new_indexed_db_manager(None).expect("IndexedDB manager");
+        let document_url = Url::parse("https://example.com/indexed-db-retired-notification")?;
+        let (mut page_vm, _resource_source, _owner_wake_rx) =
+            page_vm_with_bound_task_sources_and_owner_wake(&loader, document_url);
+        install_indexed_db_manager(&mut page_vm, &manager);
+        page_vm.vm_mut().eval(r#"
+          globalThis.notificationEvents = [];
+          const frame = document.createElement('iframe');
+          frame.id = 'notification-owner';
+          document.body.appendChild(frame);
+        "#)?;
+        let child_handle = page_vm.vm().element_handle_by_id_for_test("notification-owner")
+            .expect("notification owner frame should exist");
+        let child_context = materialize_only_child_realm_execution_context_through_page_turn_for_test(
+            &mut page_vm, "notification-owner",
+        )?;
+        page_vm.vm_mut().eval_in_child_default_context(child_context, r#"
+          const open = indexedDB.open('retired-notification', 1);
+          open.onupgradeneeded = () => open.result.createObjectStore('records');
+          open.onsuccess = () => {
+            globalThis.notificationDatabase = open.result;
+            notificationDatabase.onversionchange = () => top.notificationEvents.push('unexpected-retired-callback');
+          };
+        "#)?;
+        for _ in 0..8 {
+            if page_vm.vm_mut().eval_in_child_default_context(
+                child_context, "typeof globalThis.notificationDatabase",
+            )? == "object" {
+                break;
+            }
+            assert!(run_selected_indexed_db_task_for_test(&mut page_vm, &loader)
+                .await?.is_some(), "opening the initial connection must leave a runnable task");
+        }
+        assert_eq!(page_vm.vm_mut().eval_in_child_default_context(
+            child_context, "String(notificationDatabase.version)",
+        )?, "1");
+        page_vm.vm_mut().eval(r#"
+          const upgrade = indexedDB.open('retired-notification', 2);
+          upgrade.onupgradeneeded = () => notificationEvents.push('upgrade');
+          upgrade.onblocked = () => notificationEvents.push('unexpected-blocked');
+          upgrade.onerror = () => notificationEvents.push(`error:${upgrade.error.name}`);
+          upgrade.onsuccess = () => {
+            notificationEvents.push('success');
+            upgrade.result.close();
+          };
+        "#)?;
+        // Queue the notification in the connection's realm, then retire that
+        // realm before its task can run. The requesting realm must still recheck.
+        assert!(run_selected_indexed_db_task_for_test(&mut page_vm, &loader)
+            .await?.is_some());
+        page_vm.vm_mut().retire_child_frame_realm_for_test(child_handle);
+        for _ in 0..16 {
+            if page_vm.vm_mut().eval("notificationEvents.includes('success')")? == "true" {
+                break;
+            }
+            assert!(run_selected_indexed_db_task_for_test(&mut page_vm, &loader)
+                .await?.is_some(), "a discarded notification must leave a runnable continuation");
+        }
+        assert_eq!(page_vm.vm_mut().eval("JSON.stringify(notificationEvents)")?,
+            r#"["upgrade","success"]"#);
+        Ok::<_, anyhow::Error>(())
+    }).await.expect("retiring a versionchange recipient should unblock the requesting realm");
+}
diff --git a/moli-renderer-v8/src/script_vm/tests/indexed_db.rs b/moli-renderer-v8/src/script_vm/tests/indexed_db.rs
index 6608d73e16..bf459e7d2d 100644
--- a/moli-renderer-v8/src/script_vm/tests/indexed_db.rs
+++ b/moli-renderer-v8/src/script_vm/tests/indexed_db.rs
@@ -1829,10 +1829,12 @@ async fn indexed_db_blocked_upgrade_result_database_keeps_opener_owner() {
   request.onsuccess = () => {
     globalThis.__blockedUpgradeOwnerTopDb = request.result;
     globalThis.__blockedUpgradeOwnerTopDb.onversionchange = () => {
-      const sender = new BroadcastChannel("blocked-upgrade-top-versionchange-owner");
-      sender.postMessage("top-versionchange");
-      globalThis.__blockedUpgradeOwnerTopVersionChange = "closed";
-      globalThis.__blockedUpgradeOwnerTopDb.close();
+      Promise.resolve().then(() => {
+        const sender = new BroadcastChannel("blocked-upgrade-top-versionchange-owner");
+        sender.postMessage("top-versionchange");
+        globalThis.__blockedUpgradeOwnerTopVersionChange = "closed";
+        globalThis.__blockedUpgradeOwnerTopDb.close();
+      });
     };
     globalThis.__blockedUpgradeOwnerTopReady = "ok";
   };
@@ -5860,3 +5862,104 @@ fn indexed_db_roundtrips_image_data_with_graph_identity() {
         r#"[true,true,true,2,1,"display-p3",[1,2,3,4,5,6,7,8],true,true]"#
     );
 }
+
+#[test]
+fn indexed_db_versionchange_waits_for_connection_microtasks_before_blocked() {
+    for operation in ["upgrade", "delete"] {
+        let mut vm =
+            new_storage_page_task_executor_test_vm("https://indexeddb-notification-tasks.test/");
+        vm.eval(&format!("globalThis.operation = {operation:?};"))
+            .expect("connection operation should be set");
+        vm.eval(r#"
+globalThis.notificationEvents = [];
+const first = indexedDB.open(`notifications-${operation}`, 1);
+first.onupgradeneeded = () => first.result.createObjectStore('records');
+first.onsuccess = () => {
+  const db1 = first.result;
+  const second = indexedDB.open(db1.name);
+  second.onsuccess = () => {
+    const db2 = second.result;
+    const request = operation === 'upgrade' ? indexedDB.open(db1.name, 2) : indexedDB.deleteDatabase(db1.name);
+    db1.onversionchange = event => {
+      notificationEvents.push(`first:${event.oldVersion}:${event.newVersion}`);
+      Promise.resolve().then(() => {
+        notificationEvents.push('first-microtask');
+        request.onblocked = () => {
+          notificationEvents.push('blocked');
+          db1.close();
+          db2.close();
+        };
+      });
+    };
+    db2.onversionchange = () => {
+      notificationEvents.push('second');
+      queueMicrotask(() => notificationEvents.push('second-microtask'));
+    };
+    request.onupgradeneeded = () => notificationEvents.push('upgrade');
+    request.onerror = () => notificationEvents.push(`error:${request.error.name}`);
+    request.onsuccess = () => {
+      notificationEvents.push('success');
+      if (operation === 'upgrade') request.result.close();
+    };
+  };
+};
+"#).expect("connection notifications should be scheduled");
+        let result = vm
+            .eval_after_selected_page_tasks("JSON.stringify(notificationEvents)")
+            .expect("connection notification tasks should finish");
+        let expected = if operation == "upgrade" {
+            r#"["first:1:2","first-microtask","second","second-microtask","blocked","upgrade","success"]"#
+        } else {
+            r#"["first:1:null","first-microtask","second","second-microtask","blocked","success"]"#
+        };
+        assert_eq!(result, expected, "{operation} notification order");
+    }
+}
+
+#[test]
+fn indexed_db_versionchange_skips_connections_closed_by_an_earlier_microtask() {
+    for operation in ["upgrade", "delete"] {
+        let mut vm =
+            new_storage_page_task_executor_test_vm("https://indexeddb-notification-close.test/");
+        vm.eval(&format!("globalThis.operation = {operation:?};"))
+            .expect("connection operation should be set");
+        vm.eval(r#"
+globalThis.notificationEvents = [];
+const first = indexedDB.open(`notifications-close-${operation}`, 1);
+first.onupgradeneeded = () => first.result.createObjectStore('records');
+first.onsuccess = () => {
+  const db1 = first.result;
+  const second = indexedDB.open(db1.name);
+  second.onsuccess = () => {
+    const db2 = second.result;
+    db1.onversionchange = () => {
+      notificationEvents.push('first');
+      Promise.resolve().then(() => {
+        notificationEvents.push('close-microtask');
+        db1.close();
+        db2.close();
+      });
+    };
+    db2.onversionchange = () => notificationEvents.push('unexpected-second');
+    const request = operation === 'upgrade' ? indexedDB.open(db1.name, 2) : indexedDB.deleteDatabase(db1.name);
+    request.onblocked = () => notificationEvents.push('unexpected-blocked');
+    request.onupgradeneeded = () => notificationEvents.push('upgrade');
+    request.onerror = () => notificationEvents.push(`error:${request.error.name}`);
+    request.onsuccess = () => {
+      notificationEvents.push('success');
+      if (operation === 'upgrade') request.result.close();
+    };
+  };
+};
+"#).expect("closing notification should be scheduled");
+        let result = vm
+            .eval_after_selected_page_tasks("JSON.stringify(notificationEvents)")
+            .expect("closing notification tasks should finish");
+        let expected = if operation == "upgrade" {
+            r#"["first","close-microtask","upgrade","success"]"#
+        } else {
+            r#"["first","close-microtask","success"]"#
+        };
+        assert_eq!(result, expected, "{operation} must skip closed connections");
+    }
+}