Can't edit Folder Tree's left button selection event

I stumbled upon an issue at preferences that I can't see how to change:

In preferences - Folder Tree - selection events - Left mouse button - normal is dimmed (not acessible) why?

You only have two choices for what the normal left-click action in the folder tree does, as things would easily go haywire if you could assign any command to it.

The edit field tells you what the current command is, and the checkbox below lets you change it.

For the other mouse/key actions, you can assign arbitrary commands to them, so those fields are fully editable.

Taking that into account is there anyway to configure the action when left-clicking or just selecting a folder in folder tree to let's say open it in lister in a new tab?

I don't think there is. But would you really want to? If you clicked through a few folders looking for the right one, you'd end up with a mess of tabs that had to be closed.

It could be NEWTAB=findexisting ?

You'd still end up with a lot of unwanted tabs after flicking through folders to look for something.

If you want it to jump to an existing tab if one is already open for the folder then the checkbox does just that.

Ok got it. Anyway I usually don't use the folder tree, so it's not a problem.