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diff --git a/frontend-old/node_modules/web-vitals/src/onCLS.ts b/frontend-old/node_modules/web-vitals/src/onCLS.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 {onBFCacheRestore} from './lib/bfcache.js';
+import {initMetric} from './lib/initMetric.js';
+import {observe} from './lib/observe.js';
+import {bindReporter} from './lib/bindReporter.js';
+import {doubleRAF} from './lib/doubleRAF.js';
+import {onHidden} from './lib/onHidden.js';
+import {runOnce} from './lib/runOnce.js';
+import {onFCP} from './onFCP.js';
+import {CLSMetric, MetricRatingThresholds, ReportOpts} from './types.js';
+
+/** Thresholds for CLS. See https://web.dev/articles/cls#what_is_a_good_cls_score */
+export const CLSThresholds: MetricRatingThresholds = [0.1, 0.25];
+
+/**
+ * Calculates the [CLS](https://web.dev/articles/cls) value for the current page and
+ * calls the `callback` function once the value is ready to be reported, along
+ * with all `layout-shift` performance entries that were used in the metric
+ * value calculation. The reported value is a `double` (corresponding to a
+ * [layout shift score](https://web.dev/articles/cls#layout_shift_score)).
+ *
+ * If the `reportAllChanges` configuration option is set to `true`, the
+ * `callback` function will be called as soon as the value is initially
+ * determined as well as any time the value changes throughout the page
+ * lifespan.
+ *
+ * _**Important:** CLS should be continually monitored for changes throughout
+ * the entire lifespan of a page—including if the user returns to the page after
+ * it's been hidden/backgrounded. However, since browsers often [will not fire
+ * additional callbacks once the user has backgrounded a
+ * page](https://developer.chrome.com/blog/page-lifecycle-api/#advice-hidden),
+ * `callback` is always called when the page's visibility state changes to
+ * hidden. As a result, the `callback` function might be called multiple times
+ * during the same page load._
+ */
+export const onCLS = (
+  onReport: (metric: CLSMetric) => void,
+  opts?: ReportOpts,
+) => {
+  // Set defaults
+  opts = opts || {};
+
+  // Start monitoring FCP so we can only report CLS if FCP is also reported.
+  // Note: this is done to match the current behavior of CrUX.
+  onFCP(
+    runOnce(() => {
+      let metric = initMetric('CLS', 0);
+      let report: ReturnType<typeof bindReporter>;
+
+      let sessionValue = 0;
+      let sessionEntries: LayoutShift[] = [];
+
+      const handleEntries = (entries: LayoutShift[]) => {
+        entries.forEach((entry) => {
+          // Only count layout shifts without recent user input.
+          if (!entry.hadRecentInput) {
+            const firstSessionEntry = sessionEntries[0];
+            const lastSessionEntry = sessionEntries[sessionEntries.length - 1];
+
+            // If the entry occurred less than 1 second after the previous entry
+            // and less than 5 seconds after the first entry in the session,
+            // include the entry in the current session. Otherwise, start a new
+            // session.
+            if (
+              sessionValue &&
+              entry.startTime - lastSessionEntry.startTime < 1000 &&
+              entry.startTime - firstSessionEntry.startTime < 5000
+            ) {
+              sessionValue += entry.value;
+              sessionEntries.push(entry);
+            } else {
+              sessionValue = entry.value;
+              sessionEntries = [entry];
+            }
+          }
+        });
+
+        // If the current session value is larger than the current CLS value,
+        // update CLS and the entries contributing to it.
+        if (sessionValue > metric.value) {
+          metric.value = sessionValue;
+          metric.entries = sessionEntries;
+          report();
+        }
+      };
+
+      const po = observe('layout-shift', handleEntries);
+      if (po) {
+        report = bindReporter(
+          onReport,
+          metric,
+          CLSThresholds,
+          opts!.reportAllChanges,
+        );
+
+        onHidden(() => {
+          handleEntries(po.takeRecords() as CLSMetric['entries']);
+          report(true);
+        });
+
+        // Only report after a bfcache restore if the `PerformanceObserver`
+        // successfully registered.
+        onBFCacheRestore(() => {
+          sessionValue = 0;
+          metric = initMetric('CLS', 0);
+          report = bindReporter(
+            onReport,
+            metric,
+            CLSThresholds,
+            opts!.reportAllChanges,
+          );
+
+          doubleRAF(() => report());
+        });
+
+        // Queue a task to report (if nothing else triggers a report first).
+        // This allows CLS to be reported as soon as FCP fires when
+        // `reportAllChanges` is true.
+        setTimeout(report, 0);
+      }
+    }),
+  );
+};