The Columns branch under Configuration - Display - Folder has the following options:
Synced width changing
When this option is selected and columns are resized in one pane of a folder compare, the matching column in the other pane(s) will automatically be resized accordingly.
Automatically resize columns to fit the contents
When this option is selected and a compare is executed, the columns will automatically be resized to fully display the largest members of the active columns.