'On Edit, On Load' script not running

I have been trying to hide fields in a subform 'On Edit, On Load' with no success, while the same code in the 'On Add, On Load' works fine.

So I commented the script out and just put the following in 'On Edit, On Load':

//hide Action_Items_Subform.Activity_Name;

//hide Action_Items_Subform.Activity_ID;

//hide Action_Items_Subform.Name_and_Capacity;

alert("hi");

Which should display "hi" when clicking the online edit command. Nothing happens.

Then I found other scripts not running when online editing the records, such as script within 'On User Input' and in the subform ' On Add Row' command.

Can someone please offer support as to what is going on here.