diff --git a/lib/OnyxUtils.ts b/lib/OnyxUtils.ts
index 4dc1ba2ce..6a548bb45 100644
--- a/lib/OnyxUtils.ts
+++ b/lib/OnyxUtils.ts
@@ -773,11 +773,57 @@ function reportStorageQuota(error?: Error): Promise<void> {
         });
 }
 
+// 64 KB — Chromium wraps any IndexedDB value larger than this into an external blob file
+// (application/vnd.blink-idb-value-wrapper); that file write is what fails as "Failed to write blobs".
+const IDB_VALUE_WRAP_THRESHOLD_BYTES = 64 * 1024;
+
+/**
+ * Diagnostic for UNRECOVERABLE blob-write failures: reports the key(s) in the failed write and each
+ * value's approximate serialized size (never the values themselves), so telemetry can reveal whether
+ * the failing writes are the >64 KB ones Chromium externalizes to blob files, and which keys they are.
+ */
+function summarizeFailedWritePayload(defaultParams: unknown): string {
+    try {
+        const params = defaultParams as Record<string, unknown> | undefined;
+        let pairs: Array<[string, unknown]> = [];
+        if (params && typeof params === 'object') {
+            if ('key' in params && 'value' in params) {
+                pairs = [[String(params.key), params.value]];
+            } else if ('collection' in params && params.collection && typeof params.collection === 'object') {
+                pairs = Object.entries(params.collection as Record<string, unknown>);
+            } else {
+                pairs = Object.entries(params as Record<string, unknown>);
+            }
+        }
+        const sized = pairs
+            .map(([key, value]) => {
+                let bytes = -1;
+                try {
+                    bytes = JSON.stringify(value)?.length ?? 0;
+                } catch {
+                    bytes = -1;
+                }
+                return {key, bytes};
+            })
+            .sort((a, b) => b.bytes - a.bytes);
+        const overThreshold = sized.filter((entry) => entry.bytes >= IDB_VALUE_WRAP_THRESHOLD_BYTES).length;
+        const largest = sized
+            .slice(0, 5)
+            .map((entry) => `${entry.key}=${entry.bytes}B`)
+            .join(', ');
+        return `pairs: ${sized.length}. over64KB: ${overThreshold}. largest: [${largest}].`;
+    } catch {
+        return 'payload summary unavailable.';
+    }
+}
+
 /**
  * Handles storage operation failures based on the error class (see lib/storage/errors.ts).
  * The connection layer (createStore) owns connection/transport recovery; this operation layer owns
  * capacity recovery (eviction) so that a given failure is retried by exactly one layer:
  * - INVALID_DATA: logs an alert and throws (the same data will always fail).
+ * - UNRECOVERABLE: an engine-level write fault or permanently invalid payload that no retry,
+ *   reopen, or eviction can fix — skip the write quietly (no throw, unlike INVALID_DATA).
  * - TRANSIENT / FATAL: the connection layer already retried (transient) or exhausted its heal budget
  *   and alerted (fatal). Retrying here would only re-amplify, so we skip the write quietly.
  * - CAPACITY: evicts the least recently accessed evictable key and retries, under a session-level
@@ -820,6 +866,13 @@ function retryOperation<TMethod extends RetriableOnyxOperation>(
         return Promise.resolve();
     }
 
+    if (errorClass === StorageErrorClass.UNRECOVERABLE) {
+        Logger.logInfo(
+            `Storage operation skipped retry; ${errorClass} errors cannot be recovered by retrying. Error: ${error}. onyxMethod: ${onyxMethod.name}. ${summarizeFailedWritePayload(defaultParams)}`,
+        );
+        return Promise.resolve();
+    }
+
     if (nextRetryAttempt > MAX_STORAGE_OPERATION_RETRY_ATTEMPTS) {
         Logger.logAlert(`Storage operation failed after ${MAX_STORAGE_OPERATION_RETRY_ATTEMPTS} retries. Error: ${error}. onyxMethod: ${onyxMethod.name}.`);
         return Promise.resolve();
diff --git a/lib/storage/errors.ts b/lib/storage/errors.ts
index 635f55428..9a218f28d 100644
--- a/lib/storage/errors.ts
+++ b/lib/storage/errors.ts
@@ -17,6 +17,10 @@ const StorageErrorClass = {
     CAPACITY: 'capacity',
     /** Non-serializable payload. Never retriable — the same data will always fail. */
     INVALID_DATA: 'invalidData',
+    /** Engine-level write fault or a permanently invalid payload that no retry, reopen, or
+     *  eviction can fix, and that must not crash the caller (unlike INVALID_DATA). Owner:
+     *  operation layer — skip the write quietly, never retry. */
+    UNRECOVERABLE: 'unrecoverable',
     /** Backing-store corruption. Owner: connection layer — budgeted heal, then give up. */
     FATAL: 'fatal',
     /** Unmatched by the active provider. Owner: operation layer — bounded retry, and log the shape so
diff --git a/lib/storage/providers/IDBKeyValProvider/classifyError.ts b/lib/storage/providers/IDBKeyValProvider/classifyError.ts
index 99f3c3e64..0a619b4e6 100644
--- a/lib/storage/providers/IDBKeyValProvider/classifyError.ts
+++ b/lib/storage/providers/IDBKeyValProvider/classifyError.ts
@@ -19,6 +19,13 @@ function classifyIDBError(error: unknown): ValueOf<typeof StorageErrorClass> {
         return StorageErrorClass.CAPACITY;
     }
 
+    // Chromium blob-file write failure (IOError / InvalidBlob) when externalizing large IDB
+    // values. Not disk pressure and not the caller's data — an engine-level fault; retrying
+    // never succeeds, so skip quietly instead of amplifying.
+    if (message.includes('failed to write blobs')) {
+        return StorageErrorClass.UNRECOVERABLE;
+    }
+
     // Backing-store corruption (Chromium LevelDB). Recoverable only via a budgeted reopen.
     if (message.includes('internal error opening backing store')) {
         return StorageErrorClass.FATAL;
diff --git a/tests/unit/storage/providers/classifyIDBErrorTest.ts b/tests/unit/storage/providers/classifyIDBErrorTest.ts
new file mode 100644
index 000000000..4fe695163
--- /dev/null
+++ b/tests/unit/storage/providers/classifyIDBErrorTest.ts
@@ -0,0 +1,26 @@
+import classifyIDBError from '../../../../lib/storage/providers/IDBKeyValProvider/classifyError';
+import {StorageErrorClass} from '../../../../lib/storage/errors';
+
+describe('classifyIDBError', () => {
+    it('classifies "Failed to write blobs (IOError)" as UNRECOVERABLE', () => {
+        const error = new DOMException('Failed to write blobs (IOError)', 'DataError');
+        expect(classifyIDBError(error)).toBe(StorageErrorClass.UNRECOVERABLE);
+    });
+
+    it('classifies "Failed to write blobs (InvalidBlob)" as UNRECOVERABLE', () => {
+        const error = new DOMException('Failed to write blobs (InvalidBlob)', 'DataError');
+        expect(classifyIDBError(error)).toBe(StorageErrorClass.UNRECOVERABLE);
+    });
+
+    it('classifies quota exceeded as CAPACITY', () => {
+        expect(classifyIDBError(new DOMException('quota', 'QuotaExceededError'))).toBe(StorageErrorClass.CAPACITY);
+    });
+
+    it('classifies backing-store corruption as FATAL', () => {
+        expect(classifyIDBError(new DOMException('Internal error opening backing store for indexedDB.open.', 'UnknownError'))).toBe(StorageErrorClass.FATAL);
+    });
+
+    it('classifies an unrecognized error as UNKNOWN', () => {
+        expect(classifyIDBError(new DOMException('something we have never seen', 'WeirdError'))).toBe(StorageErrorClass.UNKNOWN);
+    });
+});