From f7067e2d032362ed5b6a9fc1222661e2f5d94d10 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Fri, 2 May 2025 15:32:16 -0600
Subject: [PATCH 01/20] Enable only unicode / utf8 string tests

---
 packages/firestore/test/integration/api/database.test.ts | 2 +-
 packages/firestore/test/unit/util/misc.test.ts           | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/firestore/test/integration/api/database.test.ts b/packages/firestore/test/integration/api/database.test.ts
index 9675e02efeb..265f6d210be 100644
--- a/packages/firestore/test/integration/api/database.test.ts
+++ b/packages/firestore/test/integration/api/database.test.ts
@@ -2433,7 +2433,7 @@ apiDescribe('Database', persistence => {
     });
   });
 
-  describe('Sort unicode strings', () => {
+  describe.only('Sort unicode strings', () => {
     const expectedDocs = [
       'b',
       'a',
diff --git a/packages/firestore/test/unit/util/misc.test.ts b/packages/firestore/test/unit/util/misc.test.ts
index 0829259a8e8..45dc083272e 100644
--- a/packages/firestore/test/unit/util/misc.test.ts
+++ b/packages/firestore/test/unit/util/misc.test.ts
@@ -54,7 +54,7 @@ describe('FieldMask', () => {
   });
 });
 
-describe('CompareUtf8Strings', () => {
+describe.only('CompareUtf8Strings', () => {
   it('compareUtf8Strings should return correct results', () => {
     const errors = [];
     const seed = Math.floor(Math.random() * Number.MAX_SAFE_INTEGER);

From 2c219e55344cbbf92f1606f564b91b0f0d5808c4 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Mon, 5 May 2025 09:40:34 -0600
Subject: [PATCH 02/20] Attempting to mitigate failures caused by browser
 disconnect timout

---
 config/karma.base.js                                     | 1 +
 packages/firestore/test/integration/api/database.test.ts | 2 +-
 packages/firestore/test/unit/util/misc.test.ts           | 2 +-
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/config/karma.base.js b/config/karma.base.js
index c49b1246ed6..9d92053115f 100644
--- a/config/karma.base.js
+++ b/config/karma.base.js
@@ -53,6 +53,7 @@ const config = {
 
   // Doing 65 seconds to allow for the 20 second firestore tests
   browserNoActivityTimeout: 65000,
+  browserDisconnectTimeout: 65000,
 
   // Preprocess matching files before serving them to the browser.
   // Available preprocessors:
diff --git a/packages/firestore/test/integration/api/database.test.ts b/packages/firestore/test/integration/api/database.test.ts
index 265f6d210be..9675e02efeb 100644
--- a/packages/firestore/test/integration/api/database.test.ts
+++ b/packages/firestore/test/integration/api/database.test.ts
@@ -2433,7 +2433,7 @@ apiDescribe('Database', persistence => {
     });
   });
 
-  describe.only('Sort unicode strings', () => {
+  describe('Sort unicode strings', () => {
     const expectedDocs = [
       'b',
       'a',
diff --git a/packages/firestore/test/unit/util/misc.test.ts b/packages/firestore/test/unit/util/misc.test.ts
index 45dc083272e..0829259a8e8 100644
--- a/packages/firestore/test/unit/util/misc.test.ts
+++ b/packages/firestore/test/unit/util/misc.test.ts
@@ -54,7 +54,7 @@ describe('FieldMask', () => {
   });
 });
 
-describe.only('CompareUtf8Strings', () => {
+describe('CompareUtf8Strings', () => {
   it('compareUtf8Strings should return correct results', () => {
     const errors = [];
     const seed = Math.floor(Math.random() * Number.MAX_SAFE_INTEGER);

From d4b667eba01e53479e9529c62829c5c7a892f6e1 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Mon, 5 May 2025 11:46:42 -0600
Subject: [PATCH 03/20] Skip compareUtf8Strings should return correct results

---
 packages/firestore/test/unit/util/misc.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/firestore/test/unit/util/misc.test.ts b/packages/firestore/test/unit/util/misc.test.ts
index 0829259a8e8..982b8498611 100644
--- a/packages/firestore/test/unit/util/misc.test.ts
+++ b/packages/firestore/test/unit/util/misc.test.ts
@@ -55,7 +55,7 @@ describe('FieldMask', () => {
 });
 
 describe('CompareUtf8Strings', () => {
-  it('compareUtf8Strings should return correct results', () => {
+  it.skip('compareUtf8Strings should return correct results', () => {
     const errors = [];
     const seed = Math.floor(Math.random() * Number.MAX_SAFE_INTEGER);
     let passCount = 0;

From a4b0f8a8c5f50506becf1fee9c2a6a923e48a9f3 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Mon, 5 May 2025 12:26:14 -0600
Subject: [PATCH 04/20] Skip sort unicode strings

---
 packages/firestore/test/integration/api/database.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/firestore/test/integration/api/database.test.ts b/packages/firestore/test/integration/api/database.test.ts
index 9675e02efeb..4661745985b 100644
--- a/packages/firestore/test/integration/api/database.test.ts
+++ b/packages/firestore/test/integration/api/database.test.ts
@@ -2433,7 +2433,7 @@ apiDescribe('Database', persistence => {
     });
   });
 
-  describe('Sort unicode strings', () => {
+  describe.skip('Sort unicode strings', () => {
     const expectedDocs = [
       'b',
       'a',

From f5e632ffdfa38a78e7ef75b03c03549534df0ac9 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Mon, 5 May 2025 12:53:52 -0600
Subject: [PATCH 05/20] browserDisconnectTimeout back to default

---
 config/karma.base.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/config/karma.base.js b/config/karma.base.js
index 9d92053115f..c49b1246ed6 100644
--- a/config/karma.base.js
+++ b/config/karma.base.js
@@ -53,7 +53,6 @@ const config = {
 
   // Doing 65 seconds to allow for the 20 second firestore tests
   browserNoActivityTimeout: 65000,
-  browserDisconnectTimeout: 65000,
 
   // Preprocess matching files before serving them to the browser.
   // Available preprocessors:

From 944feac7532079315f773889cc97968c26ff65ed Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Mon, 5 May 2025 15:58:43 -0600
Subject: [PATCH 06/20] reenable compareUtf8strings unit test"

---
 packages/firestore/test/unit/util/misc.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/firestore/test/unit/util/misc.test.ts b/packages/firestore/test/unit/util/misc.test.ts
index 982b8498611..0829259a8e8 100644
--- a/packages/firestore/test/unit/util/misc.test.ts
+++ b/packages/firestore/test/unit/util/misc.test.ts
@@ -55,7 +55,7 @@ describe('FieldMask', () => {
 });
 
 describe('CompareUtf8Strings', () => {
-  it.skip('compareUtf8Strings should return correct results', () => {
+  it('compareUtf8Strings should return correct results', () => {
     const errors = [];
     const seed = Math.floor(Math.random() * Number.MAX_SAFE_INTEGER);
     let passCount = 0;

From baeb68e70a5d741f4866263cbef73b520873443c Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Mon, 5 May 2025 16:21:44 -0600
Subject: [PATCH 07/20] another test

---
 packages/firestore/test/unit/util/misc.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/firestore/test/unit/util/misc.test.ts b/packages/firestore/test/unit/util/misc.test.ts
index 0829259a8e8..d4dd1cb9326 100644
--- a/packages/firestore/test/unit/util/misc.test.ts
+++ b/packages/firestore/test/unit/util/misc.test.ts
@@ -55,7 +55,7 @@ describe('FieldMask', () => {
 });
 
 describe('CompareUtf8Strings', () => {
-  it('compareUtf8Strings should return correct results', () => {
+  it.only('compareUtf8Strings should return correct results', () => {
     const errors = [];
     const seed = Math.floor(Math.random() * Number.MAX_SAFE_INTEGER);
     let passCount = 0;

From 538f47091a16da4401b04829a07621ed1863cabb Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Wed, 7 May 2025 15:36:56 -0600
Subject: [PATCH 08/20] Reenable all tests and increase
 browserDisconnectTimeout to 65 seconds

---
 config/karma.base.js                           | 1 +
 packages/firestore/test/unit/util/misc.test.ts | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/config/karma.base.js b/config/karma.base.js
index c49b1246ed6..9d92053115f 100644
--- a/config/karma.base.js
+++ b/config/karma.base.js
@@ -53,6 +53,7 @@ const config = {
 
   // Doing 65 seconds to allow for the 20 second firestore tests
   browserNoActivityTimeout: 65000,
+  browserDisconnectTimeout: 65000,
 
   // Preprocess matching files before serving them to the browser.
   // Available preprocessors:
diff --git a/packages/firestore/test/unit/util/misc.test.ts b/packages/firestore/test/unit/util/misc.test.ts
index d4dd1cb9326..0829259a8e8 100644
--- a/packages/firestore/test/unit/util/misc.test.ts
+++ b/packages/firestore/test/unit/util/misc.test.ts
@@ -55,7 +55,7 @@ describe('FieldMask', () => {
 });
 
 describe('CompareUtf8Strings', () => {
-  it.only('compareUtf8Strings should return correct results', () => {
+  it('compareUtf8Strings should return correct results', () => {
     const errors = [];
     const seed = Math.floor(Math.random() * Number.MAX_SAFE_INTEGER);
     let passCount = 0;

From aeec17a1b4306770f4da58b2c202b6318ab594ae Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Wed, 7 May 2025 15:39:19 -0600
Subject: [PATCH 09/20] Fix IndexDbIndexManager encoding of Uint8Array in
 Safari

---
 common/api-review/util.api.md                 |   5 +
 packages/firestore/src/index/index_entry.ts   |  85 +++++--
 .../src/local/indexeddb_index_manager.ts      | 223 +++++++++---------
 .../firestore/src/local/indexeddb_schema.ts   |   6 +-
 .../src/local/indexeddb_sentinels.ts          |   6 +-
 packages/util/src/environment.ts              |  10 +
 6 files changed, 205 insertions(+), 130 deletions(-)

diff --git a/common/api-review/util.api.md b/common/api-review/util.api.md
index 0f8fc13cd3a..427cb5e174a 100644
--- a/common/api-review/util.api.md
+++ b/common/api-review/util.api.md
@@ -317,6 +317,11 @@ export function isReactNative(): boolean;
 // @public
 export function isSafari(): boolean;
 
+// Warning: (ae-missing-release-tag) "isSafariOrWebkit" is exported by the package, but it is missing a release tag (@alpha, @beta, @public, or @internal)
+//
+// @public
+export function isSafariOrWebkit(): boolean;
+
 // Warning: (ae-missing-release-tag) "issuedAtTime" is exported by the package, but it is missing a release tag (@alpha, @beta, @public, or @internal)
 //
 // @public
diff --git a/packages/firestore/src/index/index_entry.ts b/packages/firestore/src/index/index_entry.ts
index ee80276f325..e3d9477077f 100644
--- a/packages/firestore/src/index/index_entry.ts
+++ b/packages/firestore/src/index/index_entry.ts
@@ -15,15 +15,19 @@
  * limitations under the License.
  */
 
+import { isSafariOrWebkit } from '@firebase/util';
+
+import { DbIndexEntry } from '../local/indexeddb_schema';
+import { DbIndexEntryKey } from '../local/indexeddb_sentinels';
 import { DocumentKey } from '../model/document_key';
 
 /** Represents an index entry saved by the SDK in persisted storage. */
 export class IndexEntry {
   constructor(
-    readonly indexId: number,
-    readonly documentKey: DocumentKey,
-    readonly arrayValue: Uint8Array,
-    readonly directionalValue: Uint8Array
+    readonly _indexId: number,
+    readonly _documentKey: DocumentKey,
+    readonly _arrayValue: Uint8Array | number[],
+    readonly _directionalValue: Uint8Array | number[]
   ) {}
 
   /**
@@ -31,52 +35,87 @@ export class IndexEntry {
    * directional value.
    */
   successor(): IndexEntry {
-    const currentLength = this.directionalValue.length;
+    const currentLength = this._directionalValue.length;
     const newLength =
-      currentLength === 0 || this.directionalValue[currentLength - 1] === 255
+      currentLength === 0 || this._directionalValue[currentLength - 1] === 255
         ? currentLength + 1
         : currentLength;
 
     const successor = new Uint8Array(newLength);
-    successor.set(this.directionalValue, 0);
+    successor.set(this._directionalValue, 0);
     if (newLength !== currentLength) {
-      successor.set([0], this.directionalValue.length);
+      successor.set([0], this._directionalValue.length);
     } else {
       ++successor[successor.length - 1];
     }
 
     return new IndexEntry(
-      this.indexId,
-      this.documentKey,
-      this.arrayValue,
+      this._indexId,
+      this._documentKey,
+      this._arrayValue,
       successor
     );
   }
+
+  // Create a representation of the Index Entry as a DbIndexEntry
+  dbIndexEntry(
+    uid: string,
+    orderedDocumentKey: Uint8Array,
+    documentKey: DocumentKey
+  ): DbIndexEntry {
+    return {
+      indexId: this._indexId,
+      uid, // this.uid,
+      arrayValue: indexSafeUint8Array(this._arrayValue),
+      directionalValue: indexSafeUint8Array(this._directionalValue),
+      orderedDocumentKey: indexSafeUint8Array(orderedDocumentKey), // this.encodeDirectionalKey(fieldIndex, document.key),
+      documentKey: documentKey.path.toArray()
+    };
+  }
+
+  // Create a representation of the Index Entry as a DbIndexEntryKey
+  dbIndexEntryKey(
+    uid: string,
+    orderedDocumentKey: Uint8Array,
+    documentKey: DocumentKey
+  ): DbIndexEntryKey {
+    return [
+      this._indexId,
+      uid,
+      indexSafeUint8Array(this._arrayValue),
+      indexSafeUint8Array(this._directionalValue),
+      indexSafeUint8Array(orderedDocumentKey),
+      documentKey.path.toArray()
+    ];
+  }
 }
 
 export function indexEntryComparator(
   left: IndexEntry,
   right: IndexEntry
 ): number {
-  let cmp = left.indexId - right.indexId;
+  let cmp = left._indexId - right._indexId;
   if (cmp !== 0) {
     return cmp;
   }
 
-  cmp = compareByteArrays(left.arrayValue, right.arrayValue);
+  cmp = compareByteArrays(left._arrayValue, right._arrayValue);
   if (cmp !== 0) {
     return cmp;
   }
 
-  cmp = compareByteArrays(left.directionalValue, right.directionalValue);
+  cmp = compareByteArrays(left._directionalValue, right._directionalValue);
   if (cmp !== 0) {
     return cmp;
   }
 
-  return DocumentKey.comparator(left.documentKey, right.documentKey);
+  return DocumentKey.comparator(left._documentKey, right._documentKey);
 }
 
-export function compareByteArrays(left: Uint8Array, right: Uint8Array): number {
+export function compareByteArrays(
+  left: Uint8Array | number[],
+  right: Uint8Array | number[]
+): number {
   for (let i = 0; i < left.length && i < right.length; ++i) {
     const compare = left[i] - right[i];
     if (compare !== 0) {
@@ -85,3 +124,17 @@ export function compareByteArrays(left: Uint8Array, right: Uint8Array): number {
   }
   return left.length - right.length;
 }
+
+// Create an safe representation of Uint8Array values
+// If the browser is detected as Safari or WebKit, then
+// the input array will be converted to `number[]`.
+// Otherwise, the input array will be returned in its
+// original type.
+export function indexSafeUint8Array(
+  array: Uint8Array | number[]
+): Uint8Array | number[] {
+  if (isSafariOrWebkit() && !Array.isArray(array)) {
+    return Array.from(array);
+  }
+  return array;
+}
diff --git a/packages/firestore/src/local/indexeddb_index_manager.ts b/packages/firestore/src/local/indexeddb_index_manager.ts
index d2b8bc47163..4b497a268d6 100644
--- a/packages/firestore/src/local/indexeddb_index_manager.ts
+++ b/packages/firestore/src/local/indexeddb_index_manager.ts
@@ -39,7 +39,11 @@ import {
 } from '../core/target';
 import { FirestoreIndexValueWriter } from '../index/firestore_index_value_writer';
 import { IndexByteEncoder } from '../index/index_byte_encoder';
-import { IndexEntry, indexEntryComparator } from '../index/index_entry';
+import {
+  IndexEntry,
+  indexEntryComparator,
+  indexSafeUint8Array
+} from '../index/index_entry';
 import { documentKeySet, DocumentMap } from '../model/collections';
 import { Document } from '../model/document';
 import { DocumentKey } from '../model/document_key';
@@ -294,79 +298,90 @@ export class IndexedDbIndexManager implements IndexManager {
     let canServeTarget = true;
     const indexes = new Map<Target, FieldIndex | null>();
 
-    return PersistencePromise.forEach(
-      this.getSubTargets(target),
-      (subTarget: Target) => {
-        return this.getFieldIndex(transaction, subTarget).next(index => {
-          canServeTarget &&= !!index;
-          indexes.set(subTarget, index);
-        });
-      }
-    ).next(() => {
-      if (!canServeTarget) {
-        return PersistencePromise.resolve(null as DocumentKey[] | null);
-      } else {
-        let existingKeys = documentKeySet();
-        const result: DocumentKey[] = [];
-        return PersistencePromise.forEach(indexes, (index, subTarget) => {
-          logDebug(
-            LOG_TAG,
-            `Using index ${fieldIndexToString(
-              index!
-            )} to execute ${canonifyTarget(target)}`
-          );
-
-          const arrayValues = targetGetArrayValues(subTarget, index!);
-          const notInValues = targetGetNotInValues(subTarget, index!);
-          const lowerBound = targetGetLowerBound(subTarget, index!);
-          const upperBound = targetGetUpperBound(subTarget, index!);
-
-          const lowerBoundEncoded = this.encodeBound(
-            index!,
-            subTarget,
-            lowerBound
-          );
-          const upperBoundEncoded = this.encodeBound(
-            index!,
-            subTarget,
-            upperBound
-          );
-          const notInEncoded = this.encodeValues(
-            index!,
-            subTarget,
-            notInValues
-          );
-
-          const indexRanges = this.generateIndexRanges(
-            index!.indexId,
-            arrayValues,
-            lowerBoundEncoded,
-            lowerBound.inclusive,
-            upperBoundEncoded,
-            upperBound.inclusive,
-            notInEncoded
-          );
-          return PersistencePromise.forEach(
-            indexRanges,
-            (indexRange: IDBKeyRange) => {
-              return indexEntries
-                .loadFirst(indexRange, target.limit)
-                .next(entries => {
-                  entries.forEach(entry => {
-                    const documentKey = DocumentKey.fromSegments(
-                      entry.documentKey
-                    );
-                    if (!existingKeys.has(documentKey)) {
-                      existingKeys = existingKeys.add(documentKey);
-                      result.push(documentKey);
-                    }
+    return indexEntries
+      .count()
+      .next(count => {
+        //console.log(`INDEX ENTRY COUNT: ${count}`);
+        return PersistencePromise.forEach(
+          this.getSubTargets(target),
+          (subTarget: Target) => {
+            return this.getFieldIndex(transaction, subTarget).next(index => {
+              canServeTarget &&= !!index;
+              indexes.set(subTarget, index);
+            });
+          }
+        );
+      })
+      .next(() => {
+        if (!canServeTarget) {
+          return PersistencePromise.resolve(null as DocumentKey[] | null);
+        } else {
+          let existingKeys = documentKeySet();
+          const result: DocumentKey[] = [];
+          return PersistencePromise.forEach(indexes, (index, subTarget) => {
+            logDebug(
+              LOG_TAG,
+              `Using index ${fieldIndexToString(
+                index!
+              )} to execute ${canonifyTarget(target)}`
+            );
+
+            const arrayValues = targetGetArrayValues(subTarget, index!);
+            const notInValues = targetGetNotInValues(subTarget, index!);
+            const lowerBound = targetGetLowerBound(subTarget, index!);
+            const upperBound = targetGetUpperBound(subTarget, index!);
+
+            const lowerBoundEncoded = this.encodeBound(
+              index!,
+              subTarget,
+              lowerBound
+            );
+            const upperBoundEncoded = this.encodeBound(
+              index!,
+              subTarget,
+              upperBound
+            );
+            const notInEncoded = this.encodeValues(
+              index!,
+              subTarget,
+              notInValues
+            );
+
+            const indexRanges = this.generateIndexRanges(
+              index!.indexId,
+              arrayValues,
+              lowerBoundEncoded,
+              lowerBound.inclusive,
+              upperBoundEncoded,
+              upperBound.inclusive,
+              notInEncoded
+            );
+            return PersistencePromise.forEach(
+              indexRanges,
+              (indexRange: IDBKeyRange) => {
+                // console.log(`indexRange lower: ${JSON.stringify(indexRange.lower)}, upper: ${JSON.stringify(indexRange.upper)}`);
+                // console.log(`indexRange lower: ${JSON.stringify(indexRange.lower[2])}, upper: ${JSON.stringify(indexRange.upper[2])}`);
+                // console.log(`indexRange lower: ${JSON.stringify(indexRange.lowerOpen)}, upper: ${JSON.stringify(indexRange.upperOpen)}`);
+                // console.log(`target.limit: ${target.limit}`);
+                return indexEntries
+                  .loadFirst(indexRange, target.limit)
+                  .next(entries => {
+                    // console.log(JSON.stringify(entries));
+                    entries.forEach(entry => {
+                      const documentKey = DocumentKey.fromSegments(
+                        entry.documentKey
+                      );
+                      if (!existingKeys.has(documentKey)) {
+                        existingKeys = existingKeys.add(documentKey);
+                        result.push(documentKey);
+                      }
+                    });
                   });
-                });
-            }
-          );
-        }).next(() => result as DocumentKey[] | null);
-      }
-    });
+              }
+            );
+          }).next(() => result as DocumentKey[] | null);
+        }
+      });
   }
 
   private getSubTargets(target: Target): Target[] {
@@ -460,8 +475,8 @@ export class IndexedDbIndexManager implements IndexManager {
   /** Generates the lower bound for `arrayValue` and `directionalValue`. */
   private generateLowerBound(
     indexId: number,
-    arrayValue: Uint8Array,
-    directionalValue: Uint8Array,
+    arrayValue: Uint8Array | number[],
+    directionalValue: Uint8Array | number[],
     inclusive: boolean
   ): IndexEntry {
     const entry = new IndexEntry(
@@ -476,8 +491,8 @@ export class IndexedDbIndexManager implements IndexManager {
   /** Generates the upper bound for `arrayValue` and `directionalValue`. */
   private generateUpperBound(
     indexId: number,
-    arrayValue: Uint8Array,
-    directionalValue: Uint8Array,
+    arrayValue: Uint8Array | number[],
+    directionalValue: Uint8Array | number[],
     inclusive: boolean
   ): IndexEntry {
     const entry = new IndexEntry(
@@ -817,14 +832,13 @@ export class IndexedDbIndexManager implements IndexManager {
     indexEntry: IndexEntry
   ): PersistencePromise<void> {
     const indexEntries = indexEntriesStore(transaction);
-    return indexEntries.put({
-      indexId: indexEntry.indexId,
-      uid: this.uid,
-      arrayValue: indexEntry.arrayValue,
-      directionalValue: indexEntry.directionalValue,
-      orderedDocumentKey: this.encodeDirectionalKey(fieldIndex, document.key),
-      documentKey: document.key.path.toArray()
-    });
+    return indexEntries.put(
+      indexEntry.dbIndexEntry(
+        this.uid,
+        this.encodeDirectionalKey(fieldIndex, document.key),
+        document.key
+      )
+    );
   }
 
   private deleteIndexEntry(
@@ -834,14 +848,13 @@ export class IndexedDbIndexManager implements IndexManager {
     indexEntry: IndexEntry
   ): PersistencePromise<void> {
     const indexEntries = indexEntriesStore(transaction);
-    return indexEntries.delete([
-      indexEntry.indexId,
-      this.uid,
-      indexEntry.arrayValue,
-      indexEntry.directionalValue,
-      this.encodeDirectionalKey(fieldIndex, document.key),
-      document.key.path.toArray()
-    ]);
+    return indexEntries.delete(
+      indexEntry.dbIndexEntryKey(
+        this.uid,
+        this.encodeDirectionalKey(fieldIndex, document.key),
+        document.key
+      )
+    );
   }
 
   private getExistingIndexEntries(
@@ -858,7 +871,9 @@ export class IndexedDbIndexManager implements IndexManager {
           range: IDBKeyRange.only([
             fieldIndex.indexId,
             this.uid,
-            this.encodeDirectionalKey(fieldIndex, documentKey)
+            indexSafeUint8Array(
+              this.encodeDirectionalKey(fieldIndex, documentKey)
+            )
           ])
         },
         (_, entry) => {
@@ -1020,24 +1035,16 @@ export class IndexedDbIndexManager implements IndexManager {
         return [];
       }
 
-      const lowerBound = [
-        bounds[i].indexId,
+      const lowerBound = bounds[i].dbIndexEntryKey(
         this.uid,
-        bounds[i].arrayValue,
-        bounds[i].directionalValue,
         EMPTY_VALUE,
-        []
-      ] as DbIndexEntryKey;
-
-      const upperBound = [
-        bounds[i + 1].indexId,
+        DocumentKey.empty()
+      );
+      const upperBound = bounds[i + 1].dbIndexEntryKey(
         this.uid,
-        bounds[i + 1].arrayValue,
-        bounds[i + 1].directionalValue,
         EMPTY_VALUE,
-        []
-      ] as DbIndexEntryKey;
-
+        DocumentKey.empty()
+      );
       ranges.push(IDBKeyRange.bound(lowerBound, upperBound));
     }
     return ranges;
diff --git a/packages/firestore/src/local/indexeddb_schema.ts b/packages/firestore/src/local/indexeddb_schema.ts
index 0395756ab96..24bf7050c85 100644
--- a/packages/firestore/src/local/indexeddb_schema.ts
+++ b/packages/firestore/src/local/indexeddb_schema.ts
@@ -507,14 +507,14 @@ export interface DbIndexEntry {
   /** The user id for this entry. */
   uid: string;
   /** The encoded array index value for this entry. */
-  arrayValue: Uint8Array;
+  arrayValue: Uint8Array | number[];
   /** The encoded directional value for equality and inequality filters. */
-  directionalValue: Uint8Array;
+  directionalValue: Uint8Array | number[];
   /**
    * The document key this entry points to. This entry is encoded by an ordered
    * encoder to match the key order of the index.
    */
-  orderedDocumentKey: Uint8Array;
+  orderedDocumentKey: Uint8Array | number[];
   /** The segments of the document key this entry points to. */
   documentKey: string[];
 }
diff --git a/packages/firestore/src/local/indexeddb_sentinels.ts b/packages/firestore/src/local/indexeddb_sentinels.ts
index cb6ebcb664a..c35f111df2e 100644
--- a/packages/firestore/src/local/indexeddb_sentinels.ts
+++ b/packages/firestore/src/local/indexeddb_sentinels.ts
@@ -313,9 +313,9 @@ export const DbIndexStateSequenceNumberIndexPath = ['uid', 'sequenceNumber'];
 export type DbIndexEntryKey = [
   number,
   string,
-  Uint8Array,
-  Uint8Array,
-  Uint8Array,
+  Uint8Array | number[],
+  Uint8Array | number[],
+  Uint8Array | number[],
   string[]
 ];
 
diff --git a/packages/util/src/environment.ts b/packages/util/src/environment.ts
index a0467b08c59..0824b2eceda 100644
--- a/packages/util/src/environment.ts
+++ b/packages/util/src/environment.ts
@@ -173,6 +173,16 @@ export function isSafari(): boolean {
   );
 }
 
+/** Returns true if we are running in Safari or WebKit */
+export function isSafariOrWebkit(): boolean {
+  return (
+    !isNode() &&
+    !!navigator.userAgent &&
+    (navigator.userAgent.includes('Safari') || navigator.userAgent.includes('WebKit')) &&
+    !navigator.userAgent.includes('Chrome')
+  );
+}
+
 /**
  * This method checks if indexedDB is supported by current browser/service worker context
  * @return true if indexedDB is supported by current browser/service worker context

From 385478504c6c210a8343e93fff12d3568996a1b2 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Wed, 7 May 2025 15:40:03 -0600
Subject: [PATCH 10/20] Scripts for running tests in WebKit locally

---
 packages/firestore/package.json | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/packages/firestore/package.json b/packages/firestore/package.json
index 8cc7e5e18f5..4fc4a9dc1ed 100644
--- a/packages/firestore/package.json
+++ b/packages/firestore/package.json
@@ -36,6 +36,8 @@
     "test:browser:emulator": "karma start --targetBackend=emulator",
     "test:browser:nightly": "karma start --targetBackend=nightly",
     "test:browser:prod": "karma start --targetBackend=prod",
+    "test:webkit:prod": "BROWSERS=WebkitHeadless karma start --targetBackend=prod --browsers=WebkitHeadless",
+    "test:webkit:unit": "BROWSERS=WebkitHeadless karma start --unit --targetBackend=prod --browsers=WebkitHeadless",
     "test:browser:prod:nameddb": "karma start --targetBackend=prod --databaseId=test-db",
     "test:browser:unit": "karma start --unit",
     "test:browser:debug": "karma start --browsers=Chrome --auto-watch",

From 53ecb6780c136c4667fe5f1da029332b9e2248ef Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Wed, 7 May 2025 16:03:58 -0600
Subject: [PATCH 11/20] lint fix

---
 packages/firestore/test/integration/api/database.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/firestore/test/integration/api/database.test.ts b/packages/firestore/test/integration/api/database.test.ts
index 4661745985b..9675e02efeb 100644
--- a/packages/firestore/test/integration/api/database.test.ts
+++ b/packages/firestore/test/integration/api/database.test.ts
@@ -2433,7 +2433,7 @@ apiDescribe('Database', persistence => {
     });
   });
 
-  describe.skip('Sort unicode strings', () => {
+  describe('Sort unicode strings', () => {
     const expectedDocs = [
       'b',
       'a',

From 44cee475dcbe9cde274a74f65970dad784390f4f Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Wed, 7 May 2025 17:39:36 -0600
Subject: [PATCH 12/20] formatting

---
 packages/util/src/environment.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/util/src/environment.ts b/packages/util/src/environment.ts
index 0824b2eceda..85410494241 100644
--- a/packages/util/src/environment.ts
+++ b/packages/util/src/environment.ts
@@ -178,7 +178,8 @@ export function isSafariOrWebkit(): boolean {
   return (
     !isNode() &&
     !!navigator.userAgent &&
-    (navigator.userAgent.includes('Safari') || navigator.userAgent.includes('WebKit')) &&
+    (navigator.userAgent.includes('Safari') ||
+      navigator.userAgent.includes('WebKit')) &&
     !navigator.userAgent.includes('Chrome')
   );
 }

From 2380e61c1436f6d8060f38c63e18df9c9d5ac1f2 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Wed, 7 May 2025 17:41:29 -0600
Subject: [PATCH 13/20] Create eighty-starfishes-listen.md

---
 .changeset/eighty-starfishes-listen.md | 6 ++++++
 1 file changed, 6 insertions(+)
 create mode 100644 .changeset/eighty-starfishes-listen.md

diff --git a/.changeset/eighty-starfishes-listen.md b/.changeset/eighty-starfishes-listen.md
new file mode 100644
index 00000000000..2ee9941c56e
--- /dev/null
+++ b/.changeset/eighty-starfishes-listen.md
@@ -0,0 +1,6 @@
+---
+"@firebase/firestore": patch
+"@firebase/util": patch
+---
+
+Fix encoding of CSI keys in Safari

From e6860acafda834c4a04f346a5b3b0613665d1cff Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Wed, 7 May 2025 17:50:45 -0600
Subject: [PATCH 14/20] cleanup

---
 packages/firestore/src/index/index_entry.ts   |   4 +-
 .../src/local/indexeddb_index_manager.ts      | 163 ++++++++----------
 2 files changed, 78 insertions(+), 89 deletions(-)

diff --git a/packages/firestore/src/index/index_entry.ts b/packages/firestore/src/index/index_entry.ts
index e3d9477077f..907beb4f388 100644
--- a/packages/firestore/src/index/index_entry.ts
+++ b/packages/firestore/src/index/index_entry.ts
@@ -65,10 +65,10 @@ export class IndexEntry {
   ): DbIndexEntry {
     return {
       indexId: this._indexId,
-      uid, // this.uid,
+      uid,
       arrayValue: indexSafeUint8Array(this._arrayValue),
       directionalValue: indexSafeUint8Array(this._directionalValue),
-      orderedDocumentKey: indexSafeUint8Array(orderedDocumentKey), // this.encodeDirectionalKey(fieldIndex, document.key),
+      orderedDocumentKey: indexSafeUint8Array(orderedDocumentKey),
       documentKey: documentKey.path.toArray()
     };
   }
diff --git a/packages/firestore/src/local/indexeddb_index_manager.ts b/packages/firestore/src/local/indexeddb_index_manager.ts
index 4b497a268d6..7d28649df2f 100644
--- a/packages/firestore/src/local/indexeddb_index_manager.ts
+++ b/packages/firestore/src/local/indexeddb_index_manager.ts
@@ -298,90 +298,79 @@ export class IndexedDbIndexManager implements IndexManager {
     let canServeTarget = true;
     const indexes = new Map<Target, FieldIndex | null>();
 
-    return indexEntries
-      .count()
-      .next(count => {
-        //console.log(`INDEX ENTRY COUNT: ${count}`);
-        return PersistencePromise.forEach(
-          this.getSubTargets(target),
-          (subTarget: Target) => {
-            return this.getFieldIndex(transaction, subTarget).next(index => {
-              canServeTarget &&= !!index;
-              indexes.set(subTarget, index);
-            });
-          }
-        );
-      })
-      .next(() => {
-        if (!canServeTarget) {
-          return PersistencePromise.resolve(null as DocumentKey[] | null);
-        } else {
-          let existingKeys = documentKeySet();
-          const result: DocumentKey[] = [];
-          return PersistencePromise.forEach(indexes, (index, subTarget) => {
-            logDebug(
-              LOG_TAG,
-              `Using index ${fieldIndexToString(
-                index!
-              )} to execute ${canonifyTarget(target)}`
-            );
-
-            const arrayValues = targetGetArrayValues(subTarget, index!);
-            const notInValues = targetGetNotInValues(subTarget, index!);
-            const lowerBound = targetGetLowerBound(subTarget, index!);
-            const upperBound = targetGetUpperBound(subTarget, index!);
-
-            const lowerBoundEncoded = this.encodeBound(
-              index!,
-              subTarget,
-              lowerBound
-            );
-            const upperBoundEncoded = this.encodeBound(
-              index!,
-              subTarget,
-              upperBound
-            );
-            const notInEncoded = this.encodeValues(
-              index!,
-              subTarget,
-              notInValues
-            );
-
-            const indexRanges = this.generateIndexRanges(
-              index!.indexId,
-              arrayValues,
-              lowerBoundEncoded,
-              lowerBound.inclusive,
-              upperBoundEncoded,
-              upperBound.inclusive,
-              notInEncoded
-            );
-            return PersistencePromise.forEach(
-              indexRanges,
-              (indexRange: IDBKeyRange) => {
-                // console.log(`indexRange lower: ${JSON.stringify(indexRange.lower)}, upper: ${JSON.stringify(indexRange.upper)}`);
-                // console.log(`indexRange lower: ${JSON.stringify(indexRange.lower[2])}, upper: ${JSON.stringify(indexRange.upper[2])}`);
-                // console.log(`indexRange lower: ${JSON.stringify(indexRange.lowerOpen)}, upper: ${JSON.stringify(indexRange.upperOpen)}`);
-                // console.log(`target.limit: ${target.limit}`);
-                return indexEntries
-                  .loadFirst(indexRange, target.limit)
-                  .next(entries => {
-                    // console.log(JSON.stringify(entries));
-                    entries.forEach(entry => {
-                      const documentKey = DocumentKey.fromSegments(
-                        entry.documentKey
-                      );
-                      if (!existingKeys.has(documentKey)) {
-                        existingKeys = existingKeys.add(documentKey);
-                        result.push(documentKey);
-                      }
-                    });
+    return PersistencePromise.forEach(
+      this.getSubTargets(target),
+      (subTarget: Target) => {
+        return this.getFieldIndex(transaction, subTarget).next(index => {
+          canServeTarget &&= !!index;
+          indexes.set(subTarget, index);
+        });
+      }
+    ).next(() => {
+      if (!canServeTarget) {
+        return PersistencePromise.resolve(null as DocumentKey[] | null);
+      } else {
+        let existingKeys = documentKeySet();
+        const result: DocumentKey[] = [];
+        return PersistencePromise.forEach(indexes, (index, subTarget) => {
+          logDebug(
+            LOG_TAG,
+            `Using index ${fieldIndexToString(
+              index!
+            )} to execute ${canonifyTarget(target)}`
+          );
+
+          const arrayValues = targetGetArrayValues(subTarget, index!);
+          const notInValues = targetGetNotInValues(subTarget, index!);
+          const lowerBound = targetGetLowerBound(subTarget, index!);
+          const upperBound = targetGetUpperBound(subTarget, index!);
+
+          const lowerBoundEncoded = this.encodeBound(
+            index!,
+            subTarget,
+            lowerBound
+          );
+          const upperBoundEncoded = this.encodeBound(
+            index!,
+            subTarget,
+            upperBound
+          );
+          const notInEncoded = this.encodeValues(
+            index!,
+            subTarget,
+            notInValues
+          );
+
+          const indexRanges = this.generateIndexRanges(
+            index!.indexId,
+            arrayValues,
+            lowerBoundEncoded,
+            lowerBound.inclusive,
+            upperBoundEncoded,
+            upperBound.inclusive,
+            notInEncoded
+          );
+          return PersistencePromise.forEach(
+            indexRanges,
+            (indexRange: IDBKeyRange) => {
+              return indexEntries
+                .loadFirst(indexRange, target.limit)
+                .next(entries => {
+                  entries.forEach(entry => {
+                    const documentKey = DocumentKey.fromSegments(
+                      entry.documentKey
+                    );
+                    if (!existingKeys.has(documentKey)) {
+                      existingKeys = existingKeys.add(documentKey);
+                      result.push(documentKey);
+                    }
                   });
-              }
-            );
-          }).next(() => result as DocumentKey[] | null);
-        }
-      });
+                });
+            }
+          );
+        }).next(() => result as DocumentKey[] | null);
+      }
+    });
   }
 
   private getSubTargets(target: Target): Target[] {
@@ -475,8 +464,8 @@ export class IndexedDbIndexManager implements IndexManager {
   /** Generates the lower bound for `arrayValue` and `directionalValue`. */
   private generateLowerBound(
     indexId: number,
-    arrayValue: Uint8Array | number[],
-    directionalValue: Uint8Array | number[],
+    arrayValue: Uint8Array,
+    directionalValue: Uint8Array,
     inclusive: boolean
   ): IndexEntry {
     const entry = new IndexEntry(
@@ -491,8 +480,8 @@ export class IndexedDbIndexManager implements IndexManager {
   /** Generates the upper bound for `arrayValue` and `directionalValue`. */
   private generateUpperBound(
     indexId: number,
-    arrayValue: Uint8Array | number[],
-    directionalValue: Uint8Array | number[],
+    arrayValue: Uint8Array,
+    directionalValue: Uint8Array,
     inclusive: boolean
   ): IndexEntry {
     const entry = new IndexEntry(

From dfd8f221459fb804c32e8030ff7a8d2a5d8002f5 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Thu, 8 May 2025 13:47:57 -0600
Subject: [PATCH 15/20] Swap encoding of key safe bytes from number[] to
 sortable string. This improves encoding efficency by 4x.

---
 packages/firestore/src/index/index_entry.ts   | 76 ++++++++++++++-----
 .../src/local/indexeddb_index_manager.ts      |  9 ++-
 .../firestore/src/local/indexeddb_schema.ts   | 11 ++-
 .../src/local/indexeddb_schema_converter.ts   | 18 +++++
 .../src/local/indexeddb_sentinels.ts          | 22 ++++--
 5 files changed, 105 insertions(+), 31 deletions(-)

diff --git a/packages/firestore/src/index/index_entry.ts b/packages/firestore/src/index/index_entry.ts
index 907beb4f388..abac408e65f 100644
--- a/packages/firestore/src/index/index_entry.ts
+++ b/packages/firestore/src/index/index_entry.ts
@@ -18,7 +18,7 @@
 import { isSafariOrWebkit } from '@firebase/util';
 
 import { DbIndexEntry } from '../local/indexeddb_schema';
-import { DbIndexEntryKey } from '../local/indexeddb_sentinels';
+import { DbIndexEntryKey, KeySafeBytes } from '../local/indexeddb_sentinels';
 import { DocumentKey } from '../model/document_key';
 
 /** Represents an index entry saved by the SDK in persisted storage. */
@@ -26,8 +26,8 @@ export class IndexEntry {
   constructor(
     readonly _indexId: number,
     readonly _documentKey: DocumentKey,
-    readonly _arrayValue: Uint8Array | number[],
-    readonly _directionalValue: Uint8Array | number[]
+    readonly _arrayValue: Uint8Array,
+    readonly _directionalValue: Uint8Array
   ) {}
 
   /**
@@ -66,9 +66,9 @@ export class IndexEntry {
     return {
       indexId: this._indexId,
       uid,
-      arrayValue: indexSafeUint8Array(this._arrayValue),
-      directionalValue: indexSafeUint8Array(this._directionalValue),
-      orderedDocumentKey: indexSafeUint8Array(orderedDocumentKey),
+      arrayValue: encodeKeySafeBytes(this._arrayValue),
+      directionalValue: encodeKeySafeBytes(this._directionalValue),
+      orderedDocumentKey: encodeKeySafeBytes(orderedDocumentKey),
       documentKey: documentKey.path.toArray()
     };
   }
@@ -82,9 +82,9 @@ export class IndexEntry {
     return [
       this._indexId,
       uid,
-      indexSafeUint8Array(this._arrayValue),
-      indexSafeUint8Array(this._directionalValue),
-      indexSafeUint8Array(orderedDocumentKey),
+      encodeKeySafeBytes(this._arrayValue),
+      encodeKeySafeBytes(this._directionalValue),
+      encodeKeySafeBytes(orderedDocumentKey),
       documentKey.path.toArray()
     ];
   }
@@ -125,16 +125,56 @@ export function compareByteArrays(
   return left.length - right.length;
 }
 
-// Create an safe representation of Uint8Array values
-// If the browser is detected as Safari or WebKit, then
-// the input array will be converted to `number[]`.
-// Otherwise, the input array will be returned in its
-// original type.
-export function indexSafeUint8Array(
-  array: Uint8Array | number[]
-): Uint8Array | number[] {
+/**
+ * Workaround for WebKit bug: https://bugs.webkit.org/show_bug.cgi?id=292721
+ * Create a key safe representation of Uint8Array values.
+ * If the browser is detected as Safari or WebKit, then
+ * the input array will be converted to "sortable byte string".
+ * Otherwise, the input array will be returned in its original type.
+ */
+export function encodeKeySafeBytes(array: Uint8Array): KeySafeBytes {
   if (isSafariOrWebkit() && !Array.isArray(array)) {
-    return Array.from(array);
+    return encodeUint8ArrayToSortableString(array);
   }
   return array;
 }
+
+/**
+ * Reverts the key safe representation of Uint8Array (created by
+ * indexSafeUint8Array) to a normal Uint8Array.
+ */
+export function decodeKeySafeBytes(input: KeySafeBytes): Uint8Array {
+  if (typeof input !== 'string') {
+    return input;
+  }
+  return decodeSortableStringToUint8Array(input);
+}
+
+/**
+ * Encodes a Uint8Array into a "sortable byte string".
+ * A "sortable byte string" sorts in the same order as the Uint8Array.
+ * This works because JS string comparison sorts strings based on code points.
+ */
+function encodeUint8ArrayToSortableString(array: Uint8Array): string {
+  let byteString = '';
+  for (let i = 0; i < array.length; i++) {
+    byteString += String.fromCharCode(array[i]);
+  }
+
+  return byteString;
+}
+
+/**
+ * Decodes a "sortable byte string" back into a Uint8Array.
+ * A "sortable byte string" is assumed to be created where each character's
+ * Unicode code point directly corresponds to a single byte value (0-255).
+ */
+function decodeSortableStringToUint8Array(byteString: string): Uint8Array {
+  const uint8array = new Uint8Array(byteString.length);
+
+  for (let i = 0; i < byteString.length; i++) {
+    uint8array[i] = byteString.charCodeAt(i);
+  }
+
+  return uint8array;
+}
diff --git a/packages/firestore/src/local/indexeddb_index_manager.ts b/packages/firestore/src/local/indexeddb_index_manager.ts
index 7d28649df2f..2d707470b2f 100644
--- a/packages/firestore/src/local/indexeddb_index_manager.ts
+++ b/packages/firestore/src/local/indexeddb_index_manager.ts
@@ -42,7 +42,8 @@ import { IndexByteEncoder } from '../index/index_byte_encoder';
 import {
   IndexEntry,
   indexEntryComparator,
-  indexSafeUint8Array
+  encodeKeySafeBytes,
+  decodeKeySafeBytes
 } from '../index/index_entry';
 import { documentKeySet, DocumentMap } from '../model/collections';
 import { Document } from '../model/document';
@@ -860,7 +861,7 @@ export class IndexedDbIndexManager implements IndexManager {
           range: IDBKeyRange.only([
             fieldIndex.indexId,
             this.uid,
-            indexSafeUint8Array(
+            encodeKeySafeBytes(
               this.encodeDirectionalKey(fieldIndex, documentKey)
             )
           ])
@@ -870,8 +871,8 @@ export class IndexedDbIndexManager implements IndexManager {
             new IndexEntry(
               fieldIndex.indexId,
               documentKey,
-              entry.arrayValue,
-              entry.directionalValue
+              decodeKeySafeBytes(entry.arrayValue),
+              decodeKeySafeBytes(entry.directionalValue)
             )
           );
         }
diff --git a/packages/firestore/src/local/indexeddb_schema.ts b/packages/firestore/src/local/indexeddb_schema.ts
index 24bf7050c85..e98ae888ae2 100644
--- a/packages/firestore/src/local/indexeddb_schema.ts
+++ b/packages/firestore/src/local/indexeddb_schema.ts
@@ -16,6 +16,7 @@
  */
 
 import { BatchId, ListenSequenceNumber, TargetId } from '../core/types';
+import { KeySafeBytes } from '../index/index_entry';
 import { IndexKind } from '../model/field_index';
 import { BundledQuery } from '../protos/firestore_bundle_proto';
 import {
@@ -52,9 +53,11 @@ import { DbTimestampKey } from './indexeddb_sentinels';
  * 14. Add overlays.
  * 15. Add indexing support.
  * 16. Parse timestamp strings before creating index entries.
+ * 17. TODO(tomandersen)
+ * 18. Encode key safe representations of IndexEntry in DbIndexEntryStore.
  */
 
-export const SCHEMA_VERSION = 17;
+export const SCHEMA_VERSION = 18;
 
 /**
  * Wrapper class to store timestamps (seconds and nanos) in IndexedDb objects.
@@ -507,14 +510,14 @@ export interface DbIndexEntry {
   /** The user id for this entry. */
   uid: string;
   /** The encoded array index value for this entry. */
-  arrayValue: Uint8Array | number[];
+  arrayValue: KeySafeBytes;
   /** The encoded directional value for equality and inequality filters. */
-  directionalValue: Uint8Array | number[];
+  directionalValue: KeySafeBytes;
   /**
    * The document key this entry points to. This entry is encoded by an ordered
    * encoder to match the key order of the index.
    */
-  orderedDocumentKey: Uint8Array | number[];
+  orderedDocumentKey: KeySafeBytes;
   /** The segments of the document key this entry points to. */
   documentKey: string[];
 }
diff --git a/packages/firestore/src/local/indexeddb_schema_converter.ts b/packages/firestore/src/local/indexeddb_schema_converter.ts
index 7446ae7ae20..1b84fa4f2c1 100644
--- a/packages/firestore/src/local/indexeddb_schema_converter.ts
+++ b/packages/firestore/src/local/indexeddb_schema_converter.ts
@@ -15,6 +15,8 @@
  * limitations under the License.
  */
 
+import { isSafariOrWebkit } from '@firebase/util';
+
 import { User } from '../auth/user';
 import { ListenSequence } from '../core/listen_sequence';
 import { SnapshotVersion } from '../core/snapshot_version';
@@ -277,6 +279,22 @@ export class SchemaConverter implements SimpleDbSchemaConverter {
       });
     }
 
+    if (fromVersion < 18 && toVersion >= 18) {
+      // Clear the IndexEntryStores on WebKit and Safari to remove possibly
+      // corrupted index entries
+      if (isSafariOrWebkit()) {
+        p = p
+          .next(() => {
+            const indexStateStore = txn.objectStore(DbIndexStateStore);
+            indexStateStore.clear();
+          })
+          .next(() => {
+            const indexEntryStore = txn.objectStore(DbIndexEntryStore);
+            indexEntryStore.clear();
+          });
+      }
+    }
+
     return p;
   }
 
diff --git a/packages/firestore/src/local/indexeddb_sentinels.ts b/packages/firestore/src/local/indexeddb_sentinels.ts
index c35f111df2e..0b4f5ed8918 100644
--- a/packages/firestore/src/local/indexeddb_sentinels.ts
+++ b/packages/firestore/src/local/indexeddb_sentinels.ts
@@ -305,6 +305,15 @@ export const DbIndexStateSequenceNumberIndex = 'sequenceNumberIndex';
 
 export const DbIndexStateSequenceNumberIndexPath = ['uid', 'sequenceNumber'];
 
+/**
+ * Representation of a byte array that is safe for
+ * use in an IndexedDb key. The value is either
+ * a "sortable byte string", which is key safe in
+ * Safari/WebKit, or the value is a Uint8Array,
+ * which is key safe in other browsers.
+ */
+export type KeySafeBytes = Uint8Array | string;
+
 /**
  * The key for each index entry consists of the index id and its user id,
  * the encoded array and directional value for the indexed fields as well as
@@ -313,9 +322,9 @@ export const DbIndexStateSequenceNumberIndexPath = ['uid', 'sequenceNumber'];
 export type DbIndexEntryKey = [
   number,
   string,
-  Uint8Array | number[],
-  Uint8Array | number[],
-  Uint8Array | number[],
+  KeySafeBytes,
+  KeySafeBytes,
+  KeySafeBytes,
   string[]
 ];
 
@@ -425,6 +434,7 @@ export const V15_STORES = [
 ];
 export const V16_STORES = V15_STORES;
 export const V17_STORES = [...V15_STORES, DbGlobalsStore];
+export const V18_STORES = V17_STORES;
 
 /**
  * The list of all default IndexedDB stores used throughout the SDK. This is
@@ -435,7 +445,9 @@ export const ALL_STORES = V12_STORES;
 
 /** Returns the object stores for the provided schema. */
 export function getObjectStores(schemaVersion: number): string[] {
-  if (schemaVersion === 17) {
+  if (schemaVersion === 18) {
+    return V18_STORES;
+  } else if (schemaVersion === 17) {
     return V17_STORES;
   } else if (schemaVersion === 16) {
     return V16_STORES;
@@ -450,6 +462,6 @@ export function getObjectStores(schemaVersion: number): string[] {
   } else if (schemaVersion === 11) {
     return V11_STORES;
   } else {
-    fail(0xeb55, 'Only schema version 11 and 12 and 13 are supported');
+    fail(0xeb55, 'Only schema versions >11 are supported');
   }
 }

From 022a55e0a169c05fda2cffc202a75be62f565e33 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Thu, 8 May 2025 13:49:40 -0600
Subject: [PATCH 16/20] Update eighty-starfishes-listen.md

---
 .changeset/eighty-starfishes-listen.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.changeset/eighty-starfishes-listen.md b/.changeset/eighty-starfishes-listen.md
index 2ee9941c56e..78801bd3c8c 100644
--- a/.changeset/eighty-starfishes-listen.md
+++ b/.changeset/eighty-starfishes-listen.md
@@ -1,6 +1,6 @@
 ---
 "@firebase/firestore": patch
-"@firebase/util": patch
+"@firebase/util": minor
 ---
 
 Fix encoding of CSI keys in Safari

From d4086bbcf4978516621e7c402b75c7e5ce3c8071 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Thu, 8 May 2025 13:51:36 -0600
Subject: [PATCH 17/20] cleanup

---
 packages/firestore/src/index/index_entry.ts | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/packages/firestore/src/index/index_entry.ts b/packages/firestore/src/index/index_entry.ts
index abac408e65f..67e1db9ef2a 100644
--- a/packages/firestore/src/index/index_entry.ts
+++ b/packages/firestore/src/index/index_entry.ts
@@ -112,10 +112,7 @@ export function indexEntryComparator(
   return DocumentKey.comparator(left._documentKey, right._documentKey);
 }
 
-export function compareByteArrays(
-  left: Uint8Array | number[],
-  right: Uint8Array | number[]
-): number {
+export function compareByteArrays(left: Uint8Array, right: Uint8Array): number {
   for (let i = 0; i < left.length && i < right.length; ++i) {
     const compare = left[i] - right[i];
     if (compare !== 0) {

From 26739c9afb3342ffaac7de936ff9927c5f53d3ea Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Thu, 8 May 2025 14:02:51 -0600
Subject: [PATCH 18/20] fix import

---
 packages/firestore/src/local/indexeddb_schema.ts | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/packages/firestore/src/local/indexeddb_schema.ts b/packages/firestore/src/local/indexeddb_schema.ts
index e98ae888ae2..b8b6c1111d8 100644
--- a/packages/firestore/src/local/indexeddb_schema.ts
+++ b/packages/firestore/src/local/indexeddb_schema.ts
@@ -16,7 +16,6 @@
  */
 
 import { BatchId, ListenSequenceNumber, TargetId } from '../core/types';
-import { KeySafeBytes } from '../index/index_entry';
 import { IndexKind } from '../model/field_index';
 import { BundledQuery } from '../protos/firestore_bundle_proto';
 import {
@@ -27,7 +26,7 @@ import {
 } from '../protos/firestore_proto_api';
 
 import { EncodedResourcePath } from './encoded_resource_path';
-import { DbTimestampKey } from './indexeddb_sentinels';
+import { DbTimestampKey, KeySafeBytes } from './indexeddb_sentinels';
 
 /**
  * Schema Version for the Web client:

From 4d5b5cc12c6a16cd57ada05fd55a14e0e6924443 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Fri, 9 May 2025 13:38:18 -0600
Subject: [PATCH 19/20] Address pr feedback

---
 packages/firestore/package.json             |  4 ++--
 packages/firestore/src/index/index_entry.ts | 17 +++++++++--------
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/packages/firestore/package.json b/packages/firestore/package.json
index a35975e6128..fdf849b996e 100644
--- a/packages/firestore/package.json
+++ b/packages/firestore/package.json
@@ -36,8 +36,8 @@
     "test:browser:emulator": "karma start --targetBackend=emulator",
     "test:browser:nightly": "karma start --targetBackend=nightly",
     "test:browser:prod": "karma start --targetBackend=prod",
-    "test:webkit:prod": "BROWSERS=WebkitHeadless karma start --targetBackend=prod --browsers=WebkitHeadless",
-    "test:webkit:unit": "BROWSERS=WebkitHeadless karma start --unit --targetBackend=prod --browsers=WebkitHeadless",
+    "test:webkit:prod": "BROWSERS=WebkitHeadless karma start --targetBackend=prod",
+    "test:webkit:unit": "BROWSERS=WebkitHeadless karma start --unit --targetBackend=prod",
     "test:browser:prod:nameddb": "karma start --targetBackend=prod --databaseId=test-db",
     "test:browser:unit": "karma start --unit",
     "test:browser:debug": "karma start --browsers=Chrome --auto-watch",
diff --git a/packages/firestore/src/index/index_entry.ts b/packages/firestore/src/index/index_entry.ts
index 67e1db9ef2a..c9f3218c65e 100644
--- a/packages/firestore/src/index/index_entry.ts
+++ b/packages/firestore/src/index/index_entry.ts
@@ -79,13 +79,14 @@ export class IndexEntry {
     orderedDocumentKey: Uint8Array,
     documentKey: DocumentKey
   ): DbIndexEntryKey {
+    const entry = this.dbIndexEntry(uid, orderedDocumentKey, documentKey);
     return [
-      this._indexId,
-      uid,
-      encodeKeySafeBytes(this._arrayValue),
-      encodeKeySafeBytes(this._directionalValue),
-      encodeKeySafeBytes(orderedDocumentKey),
-      documentKey.path.toArray()
+      entry.indexId,
+      entry.uid,
+      entry.arrayValue,
+      entry.directionalValue,
+      entry.orderedDocumentKey,
+      entry.documentKey
     ];
   }
 }
@@ -130,7 +131,7 @@ export function compareByteArrays(left: Uint8Array, right: Uint8Array): number {
  * Otherwise, the input array will be returned in its original type.
  */
 export function encodeKeySafeBytes(array: Uint8Array): KeySafeBytes {
-  if (isSafariOrWebkit() && !Array.isArray(array)) {
+  if (isSafariOrWebkit()) {
     return encodeUint8ArrayToSortableString(array);
   }
   return array;
@@ -138,7 +139,7 @@ export function encodeKeySafeBytes(array: Uint8Array): KeySafeBytes {
 
 /**
  * Reverts the key safe representation of Uint8Array (created by
- * indexSafeUint8Array) to a normal Uint8Array.
+ * encodeKeySafeBytes) to a normal Uint8Array.
  */
 export function decodeKeySafeBytes(input: KeySafeBytes): Uint8Array {
   if (typeof input !== 'string') {

From 0dc1ea617674ff116fa951d6d595e1fbee25c4c2 Mon Sep 17 00:00:00 2001
From: Mark Duckworth <1124037+MarkDuckworth@users.noreply.github.com>
Date: Fri, 9 May 2025 14:11:13 -0600
Subject: [PATCH 20/20] fix changelog

---
 .changeset/eighty-starfishes-listen.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.changeset/eighty-starfishes-listen.md b/.changeset/eighty-starfishes-listen.md
index 78801bd3c8c..4f53b0fb786 100644
--- a/.changeset/eighty-starfishes-listen.md
+++ b/.changeset/eighty-starfishes-listen.md
@@ -3,4 +3,4 @@
 "@firebase/util": minor
 ---
 
-Fix encoding of CSI keys in Safari
+Fix Safari/WebKit cache issues when client-side indexing is used.