Add a new row in a 2D array

Hello again,
Preface: I use Windows 10 and Google Chrome, I’m also very new to javascript
I want to add a row to a preexisting array that would look like thisimage —> image


The lines inside the executeScript_sandbox command: image

I get this error “Error in executeScript_Sandbox code: Cannot set property ‘0’ of undefined”

I attempted to flip the location of the input image
and got this output: image

So newArr.length is definitely reading the column length but my script is not able to input variables into the columns correctly. If anyone has a suggestion on how to add the row correctly I’d be very grateful

I found a solution: