Trouble when use FixedTableHeader for table with scroll horizontal

Hi all

As title I have a problem when tries add FixedTableHeader block for screen contain table with scroll horizontal, it make this screen zoom in and some item can read at right of screen(seems to increase in width to the right) like image bellow :

Before apply FixedTableHeader block:

After apply FixedTableHeader block:

about detail info apply :

So anybody had been resolve same trouble or experience about it can help me

Best Regard

Tung Nguyen