Frontail Log Viewer does not show details

after changing to OH3 (new installation on Rpi4) in frontail only WARN and ERRORS are displayed.
I would like to see all information as they are “Light change to 50%”, “Temperature change to 25°C”, …
Where can I find (and change) the frontail settings?

Frontail itself just does tail command on log files.
So what you are interested in is changing what is being logged.
Have a look at Logging | openHAB.

Thank you for the quick feedback!!!

It is working, when I enter the following into the console:

log:set INFO openhab.event.ItemStateChangedEvent
log:set WARN openhab.event.ItemStateEvent
log:set INFO openhab.event.ThingStatusInfoEvent

Which is the right config file to implement this? And…where can I find more events? In Event Bus | openHAB ?

Same document in the section near to the end of the file:

When you run those commands in the karaf console, karaf itself will make the changes to the config file. There is no need to edit yourself unless you want to change more than just the logging level.

One thing to note though is that by default OH will log to events.log. So something was done to change that after installation.

I could be wrong but this happened to me when I upgraded to OH3, your old logs are still looking at /var/log/openhab2/events.log when it should be /var/log/openhab/events.log
(without the 2)

check to see if it says /var/log/openhab2/events.log