AWS Toolkit Edit Run Configuration for lambda doesn't allow me to select a file

I have a lambda (implemented in Go).  When I right-click on the lambda symbol and select Modify Run Configuration and then select File in the dialog the file selector that pops up doesn't display the files in any directory I select.  It only displays directories.  The OK button never activates:

This should be a file selector, not a path selector.

I'm working around this by copying the desired file contents and pasting them in the Text block below.

This looks like a bug.