Cannot read properties of undefined (reading 'startTime') #41066
Description
Environment
SaaS (https://sentry.io/)
Version
NA
Steps to Reproduce
So I installed sentry.io on my application - I started getting this error "Cannot read properties of undefined (reading 'startTime')" however nowhere in my codebase do I use the word "startTime".
Examined my app.js to see that it is something coming from sentry.io code.
App.js
let n,r=0,a=[];const o=t=>{t.forEach((t=>{if(!t.hadRecentInput){const e=a[0],o=a[a.length-1];r&&t.startTime-o.startTime<1e3&&t.startTime-e.startTime<5e3?(r+=t.value,a.push(t)):(r=t.value,a=[t]),r>i.value&&(i.value=r,i.entries=a,n&&n())}}))},s=be("layout-shift",o);s&&(n=he(t,i,e.reportAllChanges),xe((()=>{o(s.takeRecords()),n(!0)})))})((t=>{const e=t.entries.pop();e&&(("undefined"==typeof __SENTRY_DEBUG__||__SENTRY_DEBUG__)&&a.kg.log("[Measurements] Adding CLS")
The related node_module file - node_modules/@sentry/tracing/esm/browser/web-vitals/getCLS.js - somewhere between line 50 and 71.
`// const handleEntries = (entries: Metric['entries']) => {
const handleEntries = (entries) => {
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];
}`
Seems to call the property startTime of lastSessionEntry - which might not be available. Unfortunely I cannot provide the issue share link from sentry.io, as it contains sensitive information as user ip, etc.
Expected Result
No console or tracking error from importing sentry into application.
Actual Result
Get error - Cannot read properties of undefined (reading 'startTime')