Codebase Browser
chromium
Go to App

chromium/content/browser/resources/traces_internals/trace_report_internals.html 

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>Local Traces Page</title>
  <link rel="stylesheet" href="chrome://resources/css/md_colors.css">
  <link rel="stylesheet" href="chrome://resources/css/text_defaults.css">
  <link rel="stylesheet" href="trace_report_internals.css">
  <script type="module" src="app.js"></script>
</head>
<body>
  <trace-report-app></trace-report-app>
</body>
</html>