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diff --git a/frontend-old/node_modules/web-vitals/src/attribution/onTTFB.ts b/frontend-old/node_modules/web-vitals/src/attribution/onTTFB.ts
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+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import {onTTFB as unattributedOnTTFB} from '../onTTFB.js';
+import {
+  TTFBMetric,
+  TTFBMetricWithAttribution,
+  ReportOpts,
+  TTFBAttribution,
+} from '../types.js';
+
+const attributeTTFB = (metric: TTFBMetric): TTFBMetricWithAttribution => {
+  // Use a default object if no other attribution has been set.
+  let attribution: TTFBAttribution = {
+    waitingDuration: 0,
+    cacheDuration: 0,
+    dnsDuration: 0,
+    connectionDuration: 0,
+    requestDuration: 0,
+  };
+
+  if (metric.entries.length) {
+    const navigationEntry = metric.entries[0];
+    const activationStart = navigationEntry.activationStart || 0;
+
+    // Measure from workerStart or fetchStart so any service worker startup
+    // time is included in cacheDuration (which also includes other sw time
+    // anyway, that cannot be accurately split out cross-browser).
+    const waitEnd = Math.max(
+      (navigationEntry.workerStart || navigationEntry.fetchStart) -
+        activationStart,
+      0,
+    );
+    const dnsStart = Math.max(
+      navigationEntry.domainLookupStart - activationStart,
+      0,
+    );
+    const connectStart = Math.max(
+      navigationEntry.connectStart - activationStart,
+      0,
+    );
+    const connectEnd = Math.max(
+      navigationEntry.connectEnd - activationStart,
+      0,
+    );
+
+    attribution = {
+      waitingDuration: waitEnd,
+      cacheDuration: dnsStart - waitEnd,
+      // dnsEnd usually equals connectStart but use connectStart over dnsEnd
+      // for dnsDuration in case there ever is a gap.
+      dnsDuration: connectStart - dnsStart,
+      connectionDuration: connectEnd - connectStart,
+      // There is often a gap between connectEnd and requestStart. Attribute
+      // that to requestDuration so connectionDuration remains 0 for
+      // service worker controlled requests were connectStart and connectEnd
+      // are the same.
+      requestDuration: metric.value - connectEnd,
+      navigationEntry: navigationEntry,
+    };
+  }
+
+  // Use Object.assign to set property to keep tsc happy.
+  const metricWithAttribution: TTFBMetricWithAttribution = Object.assign(
+    metric,
+    {attribution},
+  );
+  return metricWithAttribution;
+};
+
+/**
+ * Calculates the [TTFB](https://web.dev/articles/ttfb) value for the
+ * current page and calls the `callback` function once the page has loaded,
+ * along with the relevant `navigation` performance entry used to determine the
+ * value. The reported value is a `DOMHighResTimeStamp`.
+ *
+ * Note, this function waits until after the page is loaded to call `callback`
+ * in order to ensure all properties of the `navigation` entry are populated.
+ * This is useful if you want to report on other metrics exposed by the
+ * [Navigation Timing API](https://w3c.github.io/navigation-timing/). For
+ * example, the TTFB metric starts from the page's [time
+ * origin](https://www.w3.org/TR/hr-time-2/#sec-time-origin), which means it
+ * includes time spent on DNS lookup, connection negotiation, network latency,
+ * and server processing time.
+ */
+export const onTTFB = (
+  onReport: (metric: TTFBMetricWithAttribution) => void,
+  opts?: ReportOpts,
+) => {
+  unattributedOnTTFB((metric: TTFBMetric) => {
+    const metricWithAttribution = attributeTTFB(metric);
+    onReport(metricWithAttribution);
+  }, opts);
+};