No matter which log file I try, I can't see any log entries in the GUI. The screen always shows 'loading...' (see attached pic).
This is true which log file I choose:
Firewall / Plain View
Services / Intrusion Detection / Log File
Unbound DNS / Log File
System / Log Files / General, Backend, Web GUI
etc. etc.
I tried removing all logs in /var/log and rebooting. There are log files in /var/log with data in them.
Just saw this thread which identifies the problem and a patch to solve it:
https://forum.opnsense.org/index.php?topic=16078.0