diff --git a/src/client/App.tsx b/src/client/App.tsx
index a714e8a..66e7300 100644
--- a/src/client/App.tsx
+++ b/src/client/App.tsx
@@ -19,7 +19,7 @@ import { useProgress } from "./state/useProgress.ts";
 import { useDailyLog, type DailyLogMap } from "./state/useDailyLog.ts";
 import { adoptNewLanes, usePrefs } from "./state/usePrefs.ts";
 import { snapDayWidth } from "./state/zoom.ts";
-import { useCustom } from "./state/useCustom.ts";
+import { useCustom, type EventDraft } from "./state/useCustom.ts";
 import { compareRows, SORT_MODES, type Activity, type SortMode } from "./state/sort.ts";
 import {
   advanceFocus,
@@ -34,6 +34,7 @@ import { orderGames } from "./state/gameOrder.ts";
 import { GameMetaProvider, type MetaResolver } from "./state/gameMeta.tsx";
 import { metaOnTheme, useTheme } from "./state/theme.ts";
 import {
+  recordFor,
   type CustomEvents,
   type CustomGames,
   type LaneId,
@@ -692,17 +693,20 @@ export function App() {
           onNote={prog.setNote}
           onIgnore={(id) => toggleIgnored(id, openRow.event.title)}
           onClose={() => setOpenId(null)}
-          own={
-            custom.events[openRow.event.id] === undefined
-              ? undefined
-              : {
-                  record: custom.events[openRow.event.id]!,
-                  lanes: games,
-                  games: custom.games,
-                  onSave: custom.editEvent,
-                  onDelete: custom.removeEvent,
-                }
-          }
+          own={(() => {
+            // The row may be one occurrence of a rule. Marks key off the
+            // occurrence; the record to edit is the rule behind it.
+            const record = recordFor(custom.events, openRow.event.id);
+            if (record === undefined) return undefined;
+            return {
+              record,
+              lanes: games,
+              games: custom.games,
+              onSave: (_id: string, draft: EventDraft) =>
+                custom.editEvent(record.id, draft),
+              onDelete: () => custom.removeEvent(record.id),
+            };
+          })()}
         />
       )}
     </Shell>
diff --git a/src/shared/custom.ts b/src/shared/custom.ts
index c56e253..2c1918d 100644
--- a/src/shared/custom.ts
+++ b/src/shared/custom.ts
@@ -1,5 +1,5 @@
 import { z } from "zod";
-import { comesRoundEarly, Repeat } from "./recurrence.ts";
+import { comesRoundEarly, Repeat, ruleIdOf } from "./recurrence.ts";
 import type { Occurrence } from "./recurrence.ts";
 import { EventType, GachaEvent, Precision, slugify } from "./schema.ts";
 
@@ -271,3 +271,21 @@ export function asOccurrenceEvent(
     endPrecision: occurrence.endPrecision,
   };
 }
+
+/**
+ * The stored record a row belongs to, whichever kind of id it carries.
+ *
+ * A row may be one occurrence of a rule, whose id carries a `#` suffix and is
+ * deliberately not a key in the store. Marks, ignores and ticks key off that
+ * suffixed id — each time round has its own completion — but there is only ever
+ * one record to edit, and it is the rule.
+ *
+ * Total, and safe for a feed id: `ruleIdOf` returns anything without a
+ * separator unchanged, and a feed id is simply not in this store.
+ */
+export function recordFor(
+  events: CustomEvents,
+  rowId: string,
+): CustomEvent | undefined {
+  return events[ruleIdOf(rowId)];
+}
diff --git a/test/custom.test.ts b/test/custom.test.ts
index 4246f7a..cb3e2e1 100644
--- a/test/custom.test.ts
+++ b/test/custom.test.ts
@@ -10,6 +10,7 @@ import {
   mintCustomEventId,
   mintCustomGameId,
   precisionOf,
+  recordFor,
   RESERVED_ID_SEGMENTS,
   type CustomGames,
 } from "../src/shared/custom.ts";
@@ -607,3 +608,35 @@ describe("expanding rules into rows", () => {
     expect(rows).toEqual([]);
   });
 });
+
+describe("recordFor", () => {
+  const rule = ownEvent({
+    id: "myevent:k3f9qa2m01",
+    startsAt: new Date("2026-09-01T09:00:00").toISOString(),
+    startPrecision: "exact",
+    endsAt: new Date("2026-09-08T09:00:00").toISOString(),
+    endPrecision: "exact",
+    repeat: { unit: "weeks", interval: 2, until: null },
+  });
+  const store = { [rule.id]: rule };
+
+  test("an occurrence row finds the rule behind it", () => {
+    // Marks key off the occurrence — that is what gives each time round its own
+    // completion — but the record to edit is the rule. Without this the detail
+    // sheet looks up a key that does not exist and edit and delete vanish.
+    expect(recordFor(store, "myevent:k3f9qa2m01#2026-09-15")?.id).toBe("myevent:k3f9qa2m01");
+  });
+
+  test("a plain event finds itself", () => {
+    const plain = ownEvent({ id: "myevent:plain00001", repeat: null });
+    expect(recordFor({ [plain.id]: plain }, "myevent:plain00001")?.id).toBe("myevent:plain00001");
+  });
+
+  test("a feed event belongs to nobody here", () => {
+    expect(recordFor(store, "genshin:some-event:2026-09-01")).toBeUndefined();
+  });
+
+  test("an occurrence of a rule the reader has since deleted finds nothing", () => {
+    expect(recordFor({}, "myevent:k3f9qa2m01#2026-09-15")).toBeUndefined();
+  });
+});