Checkbox field with boolean type default value for checkbox

Last month I had used a grid with a boolean field and worked great … but i tried it now and I cannot seem to figure out why it does not render checkboxes when column is assigned to boolean type like here:

https://snippet.dhtmlx.com/me4y9291

On my Chrome browser on a work laptop and personal PC i see the same true and false values in the in store column and not checkboxes. I can see I may be missing files on my device web set up but why am I seeing it on DHTMLX sample snippet?

So, what minimum files are needed to get this to work? …
Is it possible to have a boolean column in a grid to have a default false value or do i need to have it in the dataset?

please advise - thanks!

EDIT: I realized after I posted that the snippet is not set up for checkboxes (missing type: boolean) so it works fine and i used a data string sample from this site and it worked…so it’s my data and I’ll have to fix the formatted array created via script…

Therefore only question I have is:

Is it possible to have a default boolean column value (false) in the grid config or do I need to have it populate the grid with a dataset and parse it?

If the value in the cell is undefined , null , NaN , 0 , "" (empty string) or false the checkbox for that cell will be unchecked
https://snippet.dhtmlx.com/eurdue9f
Any other value will be truthy and will be displayed with the checked checkbox: