diff --git a/frontend/src/ts/test/test-stats.ts b/frontend/src/ts/test/test-stats.ts
index 2644e4ee6a88..558a197acfde 100644
--- a/frontend/src/ts/test/test-stats.ts
+++ b/frontend/src/ts/test/test-stats.ts
@@ -247,7 +247,6 @@ export function removeAfkData(): void {
   const testSeconds = calculateTestSeconds();
   TestInput.keypressCountHistory.splice(testSeconds);
   TestInput.wpmHistory.splice(testSeconds);
-  TestInput.burstHistory.splice(testSeconds);
   TestInput.rawHistory.splice(testSeconds);
 }
 
diff --git a/frontend/src/ts/test/test-ui.ts b/frontend/src/ts/test/test-ui.ts
index 240562290a07..d80ed6cf9822 100644
--- a/frontend/src/ts/test/test-ui.ts
+++ b/frontend/src/ts/test/test-ui.ts
@@ -1324,14 +1324,11 @@ async function loadWordsHistory(): Promise<boolean> {
   for (let i = 0; i < inputHistoryLength + 2; i++) {
     const input = TestInput.input.getHistory(i);
     const corrected = TestInput.corrected.getHistory(i);
-    const word = TestWords.words.get(i);
+    const word = TestWords.words.get(i) ?? "";
+    const koreanRegex =
+      /[\uac00-\ud7af]|[\u1100-\u11ff]|[\u3130-\u318f]|[\ua960-\ua97f]|[\ud7b0-\ud7ff]/;
     const containsKorean =
-      input?.match(
-        /[\uac00-\ud7af]|[\u1100-\u11ff]|[\u3130-\u318f]|[\ua960-\ua97f]|[\ud7b0-\ud7ff]/g,
-      ) !== null ||
-      word?.match(
-        /[\uac00-\ud7af]|[\u1100-\u11ff]|[\u3130-\u318f]|[\ua960-\ua97f]|[\ud7b0-\ud7ff]/g,
-      ) !== null;
+      koreanRegex.test(input ?? "") || koreanRegex.test(word);
 
     const wordEl = document.createElement("div");
     wordEl.className = "word";
@@ -1376,7 +1373,7 @@ async function loadWordsHistory(): Promise<boolean> {
       }
 
       const inputCharacters = Strings.splitIntoCharacters(input);
-      const wordCharacters = Strings.splitIntoCharacters(word ?? "");
+      const wordCharacters = Strings.splitIntoCharacters(word);
       const correctedCharacters = Strings.splitIntoCharacters(corrected ?? "");
 
       let loop;