Look at the tweak doubleclick_on_library_view
Code:
# Behavior of doubleclick on the books list. Choices: open_viewer, do_nothing,
# edit_cell, edit_metadata. Selecting edit_metadata has the side effect of
# disabling editing a field using a single click.
# Default: open_viewer.
# Example: doubleclick_on_library_view = 'do_nothing'
doubleclick_on_library_view = 'open_viewer'