@@ -126,9 +126,14 @@ export class SentrySpanExporter {
 
 /** Try to flush any pending spans immediately. */
 public flush(): void {
-const finishedSpans: ReadableSpan[] = this._finishedSpanBuckets.flatMap(bucket =>
-bucket ? Array.from(bucket.spans) : [],
-);
+const finishedSpans: ReadableSpan[] = [];
+for (const bucket of this._finishedSpanBuckets) {
+if (bucket) {
+for (const span of bucket.spans) {
+finishedSpans.push(span);
+}
+}
+}
 
 this._flushSentSpanCache();
 const sentSpans = this._maybeSend(finishedSpans);