Enable checkbox mode by default when lister opens

Referring to this article, I want to know where you put this
So that whenever a lister opens, the checkbox is on. I'm fairly new to Opus so I'm not sure where to go but I do get that it is associated with opening a lister. Thanks.

Give this a try:

(Although many find using the middle mouse button in Opus is preferable, if the aim is to just not need to ctrl + left click things.)