Checkbox to left of Script Pane now showing

[areegee]

Sometime in the recent past, certainly since FM 19, the little checkbox on the far left of the script pane has gone away and I can no longer select scripts to appear in the drop down from the menu bar.  Instead, they all seem to appear.

It's a puzzlement.

 

[comment]

Ok, so you have searched the help for "scripts menu" and the very first result is: