Where are recent Warning popups logged?
You can manually check the warnings by calling the System.check API. There are a couple ways to do this:


Navigate to Help =&gt; Developer =&gt; API Explorer. Choose Entity=System and Action=check.
If you use Drupal's drush or WordPress's wp-cli, then you can run drush cvapi system.check or wp civicrm api system.check.


Using the API Explorer is probably a bit better in this case because it will run the check with you web server's PHP runtime. In some edge-cases, the web and CLI runtimes may be slightly different.