Cannot scroll the view which shows pending files in tree view

After an upgrade to Monterey the view which shows the current workspace state (think click on the top pane to show uncommitted changes and then look at the pane below) does not scroll properly, so I cannot easily click on files and examine changes.

This is a major degradation in functionality since examining merges is a key use case for ST.

The circumstances are as following

Source Tree version 4.1.9 (245) 

MacOS 12.5.1

There are large number of commits and I am viewing the pending files in tree view.

I can see th top set of files fine but when I pull the scroll bar down it just slips bak up again as if it were stuck. It certainly won't scroll to the bottom.