[Bug] some visit log missing UserId

[darkSheep404]

What happened?

we using js code to set useid in our vue app
and most page of our app need login to view
but we see some tracking log without username, and visited those page which need login

When does this happen, is it because the first few pages a user visits are pre-login pages ?

    <!-- Matomo -->
    <script>
      var _paq = window._paq = window._paq || [];
      var userString = localStorage.getItem('user');
      if (userString) {
        let userObject = JSON.parse(userString);
        let username = userObject.username;
        _paq.push(['setUserId', username]);
      }
      /* tracker methods like "setCustomDimension" should be called before "trackPageView" */
      _paq.push(['trackPageView']);
      _paq.push(['enableLinkTracking']);
      (function() {
        var u="/xxxx.com/";
        _paq.push(['setTrackerUrl', u+'matomo.php']);
        _paq.push(['setSiteId', '1']);
        var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
        g.async=true; g.src=u+'matomo.js'; s.parentNode.insertBefore(g,s);
      })();
    </script>
    <!-- End Matomo Code -->

What should happen?

visit log which visited pages after login in should have userid logged

How can this be reproduced?

currenly no idea

Matomo version

5.0.3

PHP version

8.0.30

Server operating system

docker

What browsers are you seeing the problem on?

Chrome

Computer operating system

windows

Relevant log output

No response

Validations

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• Follow our Security Policy.
• Check that there isn't already an issue that reports the same bug to avoid creating duplicates.
• The provided steps to reproduce is a minimal reproducible of the Bug.

[sgiehl]

could be related to #19927

[darkSheep404]

hi @sgiehl
Thanks for your help

But things are a little different,
The main point of this #19927 issue should be that pre-login and post-login access are split into two different VisiTiDs

But when we run into problems
There are some post-login access records with no userid
(Sometimes the same behavior records the userid,sometime not)
Because those pages can only be accessed after login
So visiting these pages without a userid is clearly not normal