When you run DISM tool, Windows creates its log and saves it on your disk. This article shows how to view DISM log files on Windows 11/10.

I'm looking for a log file viewer that can handle simultaneously viewing multiple arbitrarily wide log files. This is like 'less -S' or toggle-truncate-lines in emacs, where it *does not* do this ...

The Operational event logs (you have to dig down further in the Event Viewer to see these) contain a lot of the detail that the old USERENV.LOG file would provide.

Delete corrupt Event Viewer Log files in Windows Server Event Viewer logs can become corrupted for several reasons, including unexpected system shutdowns, malware attacks, or hardware failures.