Log Viewer - Export Log broken
This bug prevents the export of log data to a file using the Log Viewer. To reproduce, open the the Log Viewer, and update some categories or verbosity level. Then interact with paraview (e.g. create a Cone), and hit the "Refresh" button in the Log Viewer. If there are log entries, then click the "Export Log" button, provide a filename in the resulting dialog, and click Ok. Instead of a log file, some errors appear in the Output Messages window.
As indicated in the screenshot above, this error happened with the 5.12 RC3 release candidate downloaded from the website. The machine is an x86_64 running Ubuntu 20.04.