How to have a Grid with Empty Number Cell (null)

Good afternoon community,

I have a problem with the cells formatted as numbers in the Grid widget. They can have a null (empty cell) when it gets the data, but after you actually edit the cell in the grid (let's say that you write a 55 like in the OuterSpecmax column, second row), it's impossible to have an empty cell again. If I delete the value, and choose a different cell, the value from before (55 in this example) comes back. This is a big problem for me since if the cell is null, I shouldn't use it, but if it has a value, I should. Converting the column to string is not an option because of the dot/comma usual problem when parsing.

I have been checking the code of the Widget itself (the dhxgrid.runtime.js) but I can't find in which part of the code they actually check if the input is "nothing" to write back the value from before.

Regards,
Josue Nanin