Options List Style ‐ Select by middle button

Click mouse middle button

• on file list background to deselect all items.
• on an item in a file list for single selection (under a "Double-click to open an item" environment).

Note:
Default records "3" in Mouse add-on will also be invoked when you do the above. If you are confused, either opt out "Select by middle button" or remove the records.