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diff --git a/frontend-old/node_modules/web-vitals/src/onTTFB.ts b/frontend-old/node_modules/web-vitals/src/onTTFB.ts
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+/*
+ * Copyright 2020 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 {bindReporter} from './lib/bindReporter.js';
+import {initMetric} from './lib/initMetric.js';
+import {onBFCacheRestore} from './lib/bfcache.js';
+import {getNavigationEntry} from './lib/getNavigationEntry.js';
+import {MetricRatingThresholds, ReportOpts, TTFBMetric} from './types.js';
+import {getActivationStart} from './lib/getActivationStart.js';
+import {whenActivated} from './lib/whenActivated.js';
+
+/** Thresholds for TTFB. See https://web.dev/articles/ttfb#what_is_a_good_ttfb_score */
+export const TTFBThresholds: MetricRatingThresholds = [800, 1800];
+
+/**
+ * Runs in the next task after the page is done loading and/or prerendering.
+ * @param callback
+ */
+const whenReady = (callback: () => void) => {
+  if (document.prerendering) {
+    whenActivated(() => whenReady(callback));
+  } else if (document.readyState !== 'complete') {
+    addEventListener('load', () => whenReady(callback), true);
+  } else {
+    // Queue a task so the callback runs after `loadEventEnd`.
+    setTimeout(callback, 0);
+  }
+};
+
+/**
+ * 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: TTFBMetric) => void,
+  opts?: ReportOpts,
+) => {
+  // Set defaults
+  opts = opts || {};
+
+  let metric = initMetric('TTFB');
+  let report = bindReporter(
+    onReport,
+    metric,
+    TTFBThresholds,
+    opts.reportAllChanges,
+  );
+
+  whenReady(() => {
+    const navigationEntry = getNavigationEntry();
+
+    if (navigationEntry) {
+      // The activationStart reference is used because TTFB should be
+      // relative to page activation rather than navigation start if the
+      // page was prerendered. But in cases where `activationStart` occurs
+      // after the first byte is received, this time should be clamped at 0.
+      metric.value = Math.max(
+        navigationEntry.responseStart - getActivationStart(),
+        0,
+      );
+
+      metric.entries = [navigationEntry];
+      report(true);
+
+      // Only report TTFB after bfcache restores if a `navigation` entry
+      // was reported for the initial load.
+      onBFCacheRestore(() => {
+        metric = initMetric('TTFB', 0);
+        report = bindReporter(
+          onReport,
+          metric,
+          TTFBThresholds,
+          opts!.reportAllChanges,
+        );
+
+        report(true);
+      });
+    }
+  });
+};