@crndigitalradio
Note I posted this assuming you are clicking on the Details link of a 404 Error log entry.
A 404 log entry will only display data in the Details link modal window when the URL causing the 404 uses query arguments.
And it will only display query arguments data in the modal window as there is no column for this data while Select Filter = All Log Data.
Example. The following URL causes a 404 log entry to be added:
https://www.domain.com/wp_login.php?action=register
(wp_login.php file does not exist. It should be wp-login.php)
When clicking on the Details link of the resulting 404 Error log entry the modal window will show:
Query_string = Action=register
Note that if you select “404 Errors Found” as Select Filter: you can click on the first column value and get some sort of details about the 404.
dwinden